Sewerage of 

Build mas 




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COPYRIGHT DEPOSm 



THE SANITARY SEWERAGE 

OF 

BUILDINGS 



By THOMAS S. AINGE, 

Sanitary Engineer, Michigan 
Department of Health; 

Member American Society of 

Inspectors of Plumbing and 

Sanitary Engineers. 



DOMESTIC ENGINEERING 

49-53 N. Jefferson Street 

Chicago 



\ 



v* 



LIBRARY of CONGRESS 
Two CoDies Received 

MAR 8 1(109 

Oopyrignt entry 

^£- */,/</©? 

CLASS OC XXc, No, 

COPY 8. 



copyright 

Domestic Engineering 

1907 



(?-<?£? S 



The Sanitary Sewerage 
of Buildings 



CONTENTS. 



Page. 

Introduction 9 

General Principles of Sanitary Sewers. . . 13 

Outside Sewers 18 

Inside Sewers 55 

Soil, Waste and Vent Pipes 66 

Roughing-in Test, and Filling in of the 

Trenches 85 

Plumbing Fixtures and Accessories 93 

Traps 132 

Final Test and Inspection 168 

Disposal of Sewage in Unsewered Local- 
ities 174 

The Care of Private Sewers 190 



ERRATA. 

On page 49 omit second paragraph from bottom, 
reading, "It will be," etc. 

On page 68, fifth line from bottom, reading "alter- 
ation" should be "alternation." 

On page 70, the punctuation in Table 8 should be 
periods instead of commas. 



Introduction. 



"God made the country and man made the 
toicn. 

What iconder, then, that health and vir- 
tue — gifts 

That can alone make sweet the bitter 
draught 

That life holds out to all — should most 
abound, 

And least be threatened in the fields and 
groves?" — Goicper. 



f~\ F the many problems incident to modern life, 
none are so important and none so difficult of 
solution as that pertaining to the attainment and 
maintenance of a normal condition of the human 
physiology, under the man-created conditions of 
life in cities and other populous centers. 

For centuries past, men, of almost every station 
in life, have wrestled with this problem, prompted 
thereto by the invasion, or threatened invasion, of 
a locality by a dangerous epidemic disease; by the 
presentation of statistics indicating unusually high 
rates of sickness or mortality; by the desire, born 
of instinct, for self-preservation; or by the desire, 
born of philanthropy, to render life in general more 
pleasant and profitable, dying less terrible, and death 
more remote. And from the struggle have ema- 



Introduction. 

nated countless volumes and numberless theories 
relative to the conditions under which the dweller 
in a community may hope to fill out the allotted 
span of three-score years and ten in the full enjoy- 
ment of health and its attendant blessings. 

In the civilized world it was at one time generally 
believed — and this belief is still current, though to 
a much less extent — that epidemics of dangerous 
diseases were the direct visitations of a Divine 
Providence. 

With the advent of the modern sanitarian caiue 
the discovery that the source of many of the dan ■ 
gerous diseases was to be found in the air of sewers 
and drains ; and the necessity for a system of double 
trapping of house sewers, to exclude this insidious 
agent of disease and death from the dwelling, was 
urged upon the people. Laws and regulations for 
the control of plumbing and sewerage became gen- 
eral; the merits and demerits of certain methods of 
ventilating the public sewers were widely discussed ; 
charcoal baskets, for the purification of sewer air 
prior to its exit from the manholes, were recom- 
mended; extensive tests were made to determine 
the relative efficiency of certain patented devices, 
termed cowls, for the extraction of air from the 
sewers and its delivery into the air at safe points 
above the roofs of buildings ; the sewers and plumb- 
ing of large numbers of houses were subjected to 
severe tests and careful examinations — in manv in- 



10 



Introduction. 

stances reconstructed along sanitary lines — and their 
safety certified to by the representatives of the pub- 
lic health departments. And the people heaved a 
sigh of relief, and cheerfully paid the bills, 

But, alas! Swift upon the heels of this general 
movement for the exclusion of sewer air from the 
homes and haunts of mankind came the bacteriolo- 
gist, who, with the utmost sang-froid, informed the 
people that the presence in air, water and food of 
certain specific micro-organisms, and not the air of 
sewers, was responsible for what was then popu- 
larly known as the zymotic diseases. Further, that 
if these micro-organisms should gain access to the 
sewers, their tenacity was such that they would not 
readily be liberated from the sewage, or from the 
moist surfaces of the sewers. And the people ac- 
cepted the new theories with feelings of surprise, 
or with stoicism, and, we regret to state, ridicule. 

Subsequent researches have revealed to the stu- 
dent of bacteriology the individuality, habits, haunts 
and methods of transmission of the specific germs 
of many of the dangerous communicable diseases; 
and, fortified with this knowledge, the sanitarian of 
today is waging a determined warfare against these 
diseases, with varying degrees of success. 

It was learned that filth is the handmaid of dis- 
ease, because it favors the growth and development 
both of the micro-organisms of disease and the spe- 
cial carriers of infection, and tends to a deteriora- 



11 



Introduction. 

tion of the physical forces in man, hence, predis- 
posing to disease. 

It was also learned that filth and disease have 
their origin in and are disseminated, principally, 
from the home, and other places frequented by man 
for the purposes of business, recreation or refresh- 
ment ; and that, as a natural sequence, measures for 
the restriction and prevention of the filth diseases 
must, of necessity, begin with the sanitary removal 
and disposal of the excrementitious and other or- 
ganic waste matters pertaining to life in the home. 

And the problem is, as yet, but partially solved. 

Confining our attention to the question of the 
proper disposition of those substances included 
under the generic term of sewage, principally in 
so far as relates to their removal from the imme- 
diate vicinity of the dwelling, we will consider, first, 
the general principles underlying the sanitary sew- 
erage of buildings, and, in subsequent chapters, the 
means whereby this may be accomplished. 



12 



CHAPTER I. 

General Principles. 

TN the arrangement and construction of sewers 
which may properly be termed sanitary, the fol- 
lowing general considerations must be borne in 
mind and govern the construction : 

i. The Rapid and Complete Removal of the 
Sewage. — Fresh normal fecal matter, unmixed with 
urine or water, decomposes slowly, but when the 
feces and urine, or both urine and water, are mixed, 
as in sewage, the decomposition is hastened, and 
in the process very fetid odors are liberated. Apart 
from the consideration of the deleterious character 
of such effluvia, to which reference will be made 
in a subsequent paragraph, it will be apparent that 
the decomposition of sewage should not take place 
at any point in a system of sewers ventilated, as is 
usual, by openings, at the grade, in thoroughfares 
sand in the vicinity of buildings. Further, decom- 
position within a sewer would indicate stagnation 
of the sewage, due to the faulty construction of, 
or a lack of fall in, the sewer ; and stagnation means 
a deposition of the solid particles of sewage, which, 
in turn, may be the forerunners of a complete 
stoppage in the sewer. 



13 



The Sanitary Sewerage of Buildings. 

2. The Oxidation of the Organic Matters 
Constant in Sewers. — Notwithstanding- that a sewer 
may be well constructed, and the removal of the 
sewage sufficiently rapid and, in so far as prac- 
ticable, complete, there will remain, on the inside of 
the sewer, a coating of grease and other organic 
matter, the extent and thickness of which will de- 
pend, largely, upon the smoothness, or otherwise, 
of the materials of which the sewer is constructed, 
and, in the case of grease, to a considerable extent, 
upon the cooling action of the sewer and its atmos- 
phere. Decomposition of the organic coating will 
be continuous, and, in the absence of thorough ven- 
tilation of the sewer, the atmosphere of the sewer 
will be charged with foul and noxious gases. 

3. The Exclusion of Sewer Air From Houses 
and Other Occupied Buildings. — Dating back to 
a period coincident with the general introduc- 
tion of sewers, and from thence to the present 
time, the question of sewer air in its relation to 
health has been a bone of contention among the 
members of the medical profession and others in- 
terested in the subject of hygiene. Investigations, 
more or less thorough, and with varying results, 
have been carried out, and voluminous testimony 
offered, in support of, or in opposition to, the well- 
grounded belief in the dangerous character of sewer 
air ; and the present attitude of those entrusted with 
the administration of public health affairs would 



14 



General Principles. 

indicate a willingness to give the public the benefit 
of any doubt which may exist in respect to this 
question. 

It is generally believed, and with much reason, 
that the habitual breathing of air in houses to which 
sewer effluvia have access, will produce an impaired 
condition of health, by an interference with the 
proper functions of respiration, and in a derange- 
ment of the digestive organs ; and that, for this rea- 
son alone, the entrance of sewer air to our homes 
should be rendered impossible. 

That the sewer is a factor in the dissemination of 
infection, is still a matter of dispute. We have 
reason to believe, however, that typhoid fever, and 
possibly other diseases of a kindred nature, may be 
communicated through this agency, and this belief 
is shared in by men whose contributions to the 
study of preventive medicine are standard through- 
out the civilized world. 

Of the measures prescribed for the restriction and 
prevention of typhoid fever, none are considered 
of so great importance as the disinfection of the 
feces and urine, in which the typhiod germ is said 
to leave the body of the sick person. It is a fact, 
however, that, in very many instances, the disinfec- 
tion of the dejecta of persons sick from typhoid 
fever is not properly carried out, and in many other 
instances not attempted. In cities, and other locali- 
ties having a water-carried system of sewerage, 



15 



The Sanitary Sewerage of Buildings. 

these dejecta will usually be thrown into the sewers, 
and a considerable portion of the same will remain, 
as a coating, in the sewers. We are informed that 
so long as the surface of this coating remains in 
a moist condition, the germs of typhoid fever will 
not readily be given off, but that if allowed to be- 
come dry they may be liberated by air currents, and 
by them carried, through the usual openings for 
ventilation, to the outer air, or, through defects in 
the house sewers, into the dwelling. It is scarcely 
necessary to state that there are many surfaces in 
sewers where sewage, containing the germs of 
typhoid fever, may become dry, and, at certain 
times, remain in. that condition for long periods. 

4. Impermeability and Tightness of the Sein- 
ers. — In order that the solid particles in sewage 
may be conveyed to the proper outlets, and for 
the prevention of an unwholesome condition of the 
ground in which the sewers may be laid, it is essen- 
tial that the liquid sewage be retained within the 
sewers, and not allowed to percolate or leak there- 
from. 

5. Simplicity. — The use of complicated ap- 
paratus, which may easily get out of order, will 
tend to frequent interruptions in the proper working 
of the sewers ; and a multiplication of parts may, 
sooner or later, lead to confusion, or operate to pre- 
vent the free flow of sewage from, or the free move- 
ment of air in, the sewers. 



16 



General Principles. 

6. Durability. — By reason of the fact that, in 
many instances, sewers must be laid in ground 
more or less soft, or carried under the walls of 
buildings which may settle, it is essential that the 
materials of which the sewers are constructed shall 
be able to withstand a reasonable amount of strain, 
or pressure, without fracture, at any time within 
the life of the sewers. It is also essential that those 
parts of the sewers which may be above the ground 
be able to withstand a reasonable amount of rough 
usage, without fracture, or a separation of the parts. 



.- 



17 



CHAPTER II. 

Outside Sewers. 

"DRIOR. to the construction of any sewer, a plan 
of the proposed work, showing the location, 
size and inclination of the sewer, laterals, and other 
connections, should be drawn to a convenient scale, 
and so made that it may be used not only as a work- 
ing plan but as a permanent record of the work. 
Such plans are necessary : 

i. In localities having plumbing codes, to com- 
ply with the usual requirements relative to the 
filing, with the board having jurisdiction over such 
work, of a plan, usually in duplicate, for examina- 
tion and approval, and for a permanent record. 

2. To ensure the proper and systematic construc- 
tion of the sewer. 

3. To facilitate the location of the sewer, and 
connections, at any future time, in the event of 
necessary alterations or repairs. Much time is 
usually lost in the location of sewers which have 
been laid a considerable time, especially where there 
has been a change in ownership, and, for this 
reason, a plan of the sewer should be in the posses- 
sion of the owner of every building, filed with the 
deed of the property, and transferred, with the deed, 
to any subsequent owner. 



18 



Outside Sewers. 

Curves, or bends, in a sewer are objectionable : 
i. Because they tend to prevent the rapid flow 
of sewage in the sewer. 

2. Because they are usually made with straight 
pipes, or with pipes which do not have the proper 
radius, resulting in imperfect joints. A very com- 
mon but highly improper method is shown in Fig. I . 

3. Because they render impossible the proper 
inspection of the sewer, described in a subsequent 
part of this chapter under the heading "Accessi- 
bility." 




Fig. 1. 

For the reasons mentioned, whenever possible the 
underground sewer should be laid in a perfectly 
straight line throughout its entire length. Where 
this is not practicable, the curve, or bend, should be 
made with pipes having the proper radius ; the 
radius of the entire curve, or bend, should not be 
less than ten times the cross-sectional diameter of 
the sewer; and the inclination of the sewer should 
be slightly greater in the curve, or bend, to com- 
pensate for the increased friction. 

Whenever practicable, the entire sewer trench 
should be dug before any pipes are laid and remain 



19 



The Sanitary Sewerage of Buildings. 

open until the sewer is complete and tested. A bad 
practice, and not uncommon, is the laying of the 
sewer in sections, i. e., the digging of a short length 
of the trench, laying and jointing the pipes therein, 
and filling in that portion of the trench with the dirt 
excavated for the next section of the sewer. Where 
this method is followed it will be apparent that the 
inclination of the sewer will be subject to wide 
variations ; that where earthenware pipes are used 
the filling in of the trench before the cemented 
joints have had time to harden will tend to break 
the joints, and the proper testing of the sewer will 
be an impossibility. 

It is very important that the bottom of the trench, 
which is to form the foundation of the sewer, 
should be firm and have an even slope throughout. 

If yielding earth, as "made ground," is encoun- 
tered, the bottom of the trench should be covered 
with a layer of cement concrete, not less than six 
inches in thickness, and well rammed down. 

The proper slope of the foundation of the sewer 
may be formed by the aid of a level, and a long 
narrow board, with straight edges, and wider at one 
end than the other. Thus, if the sewer is to have an 
inclination of one inch in every three feet, a board 
twelve feet long should have a difference in the 
width at each end of four inches; and by laying 
one edge of the board on the bottom of the trench, 
with the widest end toward the main sewer, and 



20 



Outside Sewers. 

leveling the upper edge, the proper slope will be 
obtained. The longer the board the more uniform 
will be the slope of the bed of the sewer. 

In the choice of materials for the construction of 
the outside sewer, the principal considerations of 
strength, thickness, smoothness, durability and im- 
permeability should govern. Brick, stone, cement 
and wood are entirely unsuited for the purpose and 
would not be permitted in any locality where the 
construction of private sewers is under municipal 
control. Earthenware (commonly known as "crock" 
or "tile") has, for more than half a century, been 
in popular favor, but is gradually giving way to the 
more suitable material, iron, and for the following 
reasons : 

Earthenware sewers are fragile and may be easily 
broken by the filling in or tamping of earth in the 
trench, or by the settlement of the earth under the 
sewers, as is well shown by the illustration of an 
excavated tile drain, shown in Fig. 2. Iron sew- 
ers, of the proper strength, could not be so frac- 
tured, except by a considerable settlement of the 
bed of earth on which they might be laid. 

The joints in earthenware sewers, as usually 
made, may, and often do, become the causes of de- 
posits in the sewers. A little cement forced into 
the interior of a sewer, and allowed to remain, may 
arrest the passage of a piece of paper, or other 
solids, and these, in turn, become the nucleus of a 



21 



The Sanitary Sewerage of Buildings. 

complete stoppage. Again, the lower portions of 
the joints being out of sight and difficult to reach, 
a small opening is often left in the cement, allowing 
liquid sewage to escape from the sewer, and a de- 
posit of solid matters to form in the vicinity of the 
leaky joints. The same result is often produced by 
the use of inferior or improperly mixed cement, 
which, becoming softened by the sewage, is grad- 
ually washed out of the lower part of the joint. 
In the jointing of iron pipes the gasket of oakum, 
which precedes the molten lead, precludes the en- 
trance to the sewer of the jointing material ; and a 
joint properly made with molten lead will be as 
tight on the bottom as in any other part, and, under 
ordinary conditions, will not be affected by the 
sewage, and will last as long as the sewer itself. 

Earthenware pipes being much shorter than iron 
pipes, necessitate the making of many more joints, 
thus adding to the cost of construction and multi- 
plying the possible sources of leakage. 

Where earthenware pipes are used for the out- 
side sewers the connections between them and the 
iron inside sewers are not easily made, and defective 
joints at these points have often proved to be the 
causes of stoppages and leaks. 

When newly laid, earthenware sewers present a 
somewhat smoother interior surface than do iron 
sewers, but after they have been in use for a time 



22 



Outside Sewers. 

both will probably be coated with grease or slime 
to an equal extent. 

In so far as relates to the lasting qualities of earth- 
enware and iron sewers, a great deal will depend 
upon the nature of the earth in which they are laid, 
the possibility of electrolytic action, and the charac- 
ter of the sewage flowing through them. Without 
considerable protection iron sewers may be readily 
weakened or destroyed by the corrosive action of 
certain soils, by electrolysis and by acids sometimes 
present in sewage. Earthenware sewers will not 
be affected to any appreciable extent by these agen- 
cies and are usually preferred to iron sewers for 
the removal of the wastes from laboratories and 
certain manufacturing establishments, from which 
strong acids may be discharged into the sewers. 
Where the danger from corrosion is outside the 
sewers, iron pipes, well coated with asphaltum, and 
further protected by a substantial ring of concrete, 
may be considered safe. 

Iron sewers are impervious both to air and water, 
and, when properly made of the best materials, 
earthenware sewers are but slightly inferior to 
them in this respect. There are, however, certain 
grades of earthenware pipes, designed for the con- 
struction of sewers, which are porous in character 
and entirely unsuited for the purpose. 

In the selection of earthenware pipes for sewers 
only those should be accepted which possess superior 

23 



The Sanitary Sewerage of Buildings. 

qualities as to strength and impermeability, and 
which are uniform in thickness, true in cross sec- 
tion, straight, well glazed inside and outside, and 
free from cracks. A good pipe will respond with a 
clear ring to a smart blow. 

By reason of their greater durability, salt glazed 
pipes are preferable to lead or glass glazed pipes. 

The proper minimum thickness and depth of hub 
for stoneware pipes is shown in Table I. Fireclay 
pipes should have a greater thickness in each case. 

Table i. 
stoneware pipes. 

Size of pipe. Minimum thickness. Minimum depth of hub. 
Inches. Inches. Inches. 

1% 
1% 

2% 
2% 
2% 
3 

It is to be regretted that in localities where 
earthenware pipes are permitted for private sewers, 
the testing of such pipes, as to the requirements 
before mentioned, is rarely attempted or included 
in the regulations governing such work. In the 
absence of municipal standards for earthenware 
pipes, or of tests relative to the qualities of the 
pipes sold in the local markets, it would be well for 

24 



3 


% 


4 


% 


6 


% 


8 


% 


10 


i 


12 


iy 8 



Outside Sewers. 

contractors and others interested in the construction 
of sewers, to obtain from the makers of such pipes 
sworn statements relative to the qualities of their 
pipes, with special reference to the amounts of 
water, if any, which they will absorb, the force re- 
quired to crush them, and their resistance to per- 
cussive action. With such information in their 
possession it should not be difficult to make selection 
of the best pipes. 

Cast iron pipes for sewers should be of the kind 
known as "Extra Heavy," the weights of which 
are shown in Table 2. 

Table 2. 
extra heavy cast iron pipes. 

Size of pipe, in inches. Weight, in pounds, per lineal foot. 

3 9y 2 

4 13 

5 17 

6 20 

7 27 

8 33% 
10 45 
12 54 

As it would be difficult to remove a defective 
length of iron pipe from the sewer after jointing, 
sand holes and weak spots should be detected, by 
hydraulic test, at the foundry, and not be left to be 
discovered by the plumber's test. 



25 



The Sanitary Sewerage of Buildings. 

Cast iron pipes and fittings for outside sewers 
should be well and thickly coated, by dipping, at the 
foundry, with asphaltum. Coal tar, pitch and lin- 
seed oil are also used, but are inferior to asphaltum. 

Wrought iron pipes, as ordinarily sold in the 
market, are not suitable for outside sewers, be- 
cause of their liability to corrosion, and for the 
further reason that the ordinary fittings are not 
recessed, and would leave rough depressions at the 
joints, and tend to the collection of solid matters 
at these points. Where wrought iron pipes are used 
for this purpose they, together with the fittings, 
should be rendered proof against corrosion by im- 
mersion, while hot, in hot liquid asphaltum, and the 
fittings should be recessed so as to make flush joints. 
The weights of such pipes should not be less than 
those shown in Table 3. 

Table 3. 
wrought iron pipes for sewers. 

Size, in inches. Weight, in pounds, per lineal foot. 

3 7i/ 2 

4 10% 

5 14% 



7 23% 

8 28% 
10 40 
12 49 

26 



Outside Sewers. 

size and inclination. 
In determining the size and inclination of the 
sewer, the following important considerations 
should govern the calculation : 

1. The sewer should be small enough and have 
the proper inclination to cause the normal flow of 
sewage to fill the sewer to such a height as will 
render it self-cleansing. 

2. The sewer should be large enough and have 
sufficient inclination to remove a considerable vol- 
ume of sewage, or rainfall, or both, in a compara- 
tively short space of time, without flooding or in- 
convenience. 

The normal and maximum flow of sewage may 
be determined within certain limits, but the rainfall 
will vary very considerably and cannot be deter- 
mined with any degree of accuracy. 

The proper amount of water necessary for 
strictly domestic purposes has been variously esti- 
mated at from twenty to thirty-three gallons per day 
for each person, and this amount may be taken as 
the normal amount of sewage to be taken care of. 
Half of this amount will probably pass into the 
sewer in six hours, and two-thirds in eight hours. 

The maximum volume of sewage will occur when 
a number of fixtures are discharged simultaneously, 
which, in a small building, is a somewhat remote 
possibility. 



27 



The Sanitary Sewerage of Buildings. 

Assuming that a bath tub containing fifty gallons 
of water, a water closet tank containing four gal- 
lons, a laundry tub containing twenty gallons, and 
a slop sink into which a two gallon pail of slops is 
thrown and which is then flushed, are all discharg- 
ing at the same time, we have a total of about 
eighty gallons of water (sewage) passing into the 
sewer in a brief space of time, probably not more 
than two minutes. By Table 4 it may be seen that 
a four-inch sewer, with an inclination of 1 in 40, 
and running full, will remove, approximately, 176 
gallons of sewage per minute, or more than four 
times the volume which would be likely to be dis- 
charged at any one time from the combined fixtures 
of a building of moderate size. And yet, in the 

Table 4. 

Approximate inclinations of circular sewers for securing 
velocities of four and one-half feet of sewage per second, when 
the sewers are running full or half full. Also the approximate 
discharge, in U. S. gallons, per minute. 

Size of sewer. Inclination. Discharge.* 

4.. 1 in 40 176 

5 1 in 50 275 

6 1 in 60 397 

7 1 in 70 540 

8 1 in 80 705 

9 1 in 90 892 

10 1 in 100 1,102 

12 1 in 120 1,586 

*When the sewers are running only half full the discharge 
will be one-half the amounts shown. 

28 



Outside Sewers. 

majority of instances, a sewer of a larger size 
would usually be provided for such a building. It 
is not wise, however, even when no rainfall is to be 
taken care of, to construct a sewer of less diameter 
than four inches, and this size is frequently stipu- 
lated in plumbing codes as the minimum size which 
will be approved. On the other hand, it is seldom 
that a size larger than six inches will be required 
for any ordinary building, and when this is the 
case, and there are considerable fluctuations in the 
volume of sewage, it would be better to use two 
sets of pipes of a small diameter than one large 
sewer, and for the following reasons : 

Up to a certain point the velocity of the sewage 
will increase with its depth in the sewer, and the 
depth of the sewage will determine its power to 
carry along the solids usually present in the sewage, 
or which may accidentally or through carelessness 
find their way into a sewer. 

A comparatively small volume of sewage which 
in a four-inch pipe might be sufficient to render it 
self-cleansing would be a shallow stream in a six- 
inch sewer, and a trickling stream in a sewer of 
larger dimensions. 

As previously stated, where the rainfall is to be 
removed by a sewer, it will be necessary to make 
the sewer large enough to remove a considerable 
quantity of water in a short space of time, the 
amount depending upon the size of the roof, or the 



29 



The Sanitary Sewerage of Buildings. 

size of that part of the lot which may be paved, and 
which may be drained into the sewer. 

The amount of rainfall is measured by means of 
a special gauge, one or more of which, together 
with the records of the local rainfall, will usually 
be found in every locality of any size, and is ex- 
pressed in inches, and in tenths and one-hundredths 
of an inch. A rainfall of one inch is that amount 
of rain which falling upon a given surface, and 
not being diminished by percolation or evaporation, 
would have a uniform depth of one inch. 

In making an estimate of the amount of water 
which will fall upon a roof, or lot, during any rain- 
storm, it will first be necessary to learn the amount 
of the rainfall, in inches, and the area of that por- 
tion of the lot covered by the building, or which 
may require to be drained, in square inches, and 
by multiplying these two numbers the number of 
cubic inches of water will be found. This may be 
converted into gallons by dividing by 231, — the ap- 
proximate number of cubic inches in a standard 
U. S. gallon of water. For example, a building 
50X25 feet would have an area of 1,250 square 
feet, or (1,250X144) 180,000 square inches, and 
180,000X1 inch of rainfall will equal 180,000 cubic 
inches, or (1 80,000-^-231) slightly more than 779 
gallons of water. 

In Michigan the average annual rainfall is about 
33.76 inches, or about 2.8 inches per month. If the 



30 



Outside Sewers. 

downfall of this amount of rain was uniform, the 
amount per day would be less than one-tenth of an 
inch, and need not be considered in the calculations 
for the sizes of private sewers. 

In the planning of sewerage systems for locali- 
ties it has been the custom of some engineers to 
provide for a rainfall of one-quarter of an inch per 
day, but even this amount would not require more 
than a passing consideration in the planning of the 
sewers of individual buildings. Neither would it 
be considered necessary to make provision for 
taking care of all the water in excessive downpours 
of rain, — as two and one-half inches in forty-five 
minutes, — because a considerable portion will over- 
flow the roof gutters and find its way into the sub- 
soil or the street channels. 

In the planning of private sewers into which the 
rainfall is to be admitted, I would suggest the 
standard of one inch of rainfall per hour as the 
maximum amount to be provided for, and such a 
rainfall could be removed from the roof or lot of 
any ordinary building, without inconvenience, by a 
properly constructed four-inch sewer. 

In some localities two sets of pipes are laid for 
the separation of the sewage and rainfall; in 
others the rainfall is collected and stored in cisterns 
— some of which have overflows to the sewers; and 
in many others, particularly in the large cities, the 
rainfall is removed principally by the sewers. 



31 



The Sanitary Sewerage of Buildings. 

From what has been said it will be seen that cal- 
culations for private sewers, based upon the actual 
amounts of sewage and rainfall to be taken care of, 
will be very unreliable and subject to wide vari- 
ations, even in the case of buildings of the same 
size and with the same class and number of plumb- 
ing fixtures. 

F"or those who wish to make further study of this 
phase of our subject it is suggested that a number 
of buildings of each of several classes, and provided 
with water meters, be selected for extended ob- 
servations. Averages of the amounts of water used 
per day for each occupant, the number of hours 
the buildings are occupied, and the amounts of rain 
falling in a given time upon the roofs, or other 
surfaces drained, would furnish valuable informa- 
tion relative to the probable amounts of sewage to 
be provided for in buildings of similar size and 
class. 

In the new plumbing code of the city of Cleve- 
land, Ohio, the number of fixtures is taken as the 
basis of the sizes of private sewers, as shown in 
Table 5. 

The inclination of a private sewer will depend 
largely upon the depth of the main sewer, and the 
distance of the latter from the highest part of the 
private sewer, and will vary considerably in the 
same sewer district. Where the total amount of 
fall is slight, the head of the sewer should be as 



32 



Outside Sewers. 

near to the surface of the ground as possible with- 
out running the risk of freezing, and where the 
amount of fall is excessive, the head of the sewer 
should be kept as low as practicable, or the sewer 
should be given a safe and uniform inclination to a 
point near to the main sewer and the inclination 
increased at this point. 

It is the unanimous opinion of engineers that the 
inclination of private sewers should be such as will 

Table 5. 

Minimum sizes of metal house sewers, for sewage and rain- 
fall, in terms of the maximum number of small fixtures, or 
their equivalents for larger ones, that may be connected there- 
with, when laid at the grades indicated. For crock house sew- 
ers the diameter is to be one size larger for the same number 
of fixtures.* 

Size of , Inclinations. — : , 

sewer. 1 in 100. 2 in 1 00. 3 in 100. 4 in 100. 

4 118 1G3 196 238 

5 216 300 364 435 

6 343 488 585 731 

7 474 722 .860 . 1,060 

8 716 1,000 1,190 1,400 

9 950 1,334 1,616 1,891 

10 1,216 1,750 2,050 2,433 

11 1,585 2,250 2,515 3,133 

12 1,950 2,725 3,310 3,900 

♦Twenty square feet of roof or yard area, in horizontal pro- 
jection, counts as one fixture. 

Three feet of urinal trough, or wash sink, counts as one 
fixture. 

One bath, basin, sink, or smaller fixture, counts as one fix- 
ture. 

One pedestal unrinal, or slop hopper sink, counts as two fix- 
tures. 

One water closet counts as two fixtures. 

33 



The Sanitary Sewerage of Buildings. 

cause a velocity of about four and one-half feet of 
sewage per second, and, for this reason, Table 4 has 
been limited to those inclinations which will give 
this velocity, or nearly so. These inclinations may 
be easily remembered by multiplying the diameter 
of the sewer by 10, the product being the length of 
sewer, to which one foot of fall should be given. 

Table 6. 

Size of Minimum 

sewer. inclination. 

4 1 in 92 

6 1 in 137 

8 1 in 183 

9 1 in 206 

10 1 in 229 

12 1 in 227 

Where the inclination oi the sewer must, of 
necessity, be small, so that the velocity of sewage 
would be less than three feet per second, the sewer 
would not be considered self-cleansing, and special 
means for flushing would be necessary to prevent 
an accumulation of deposits of solid matters. Table 
6 shows the minimum inclinations for self-cleansing 
sewers when running full or half full. 

CONNECTION WITH THE MAIN SEWER. 

In localities having modern systems of sewerage, 
stoppered openings are usually left in the main sew- 

34 



Outside Sewers. 

ers opposite to each lot, and, under such conditions, 
the connection with the main sewer would be a 
simple process. In the absence of such provision, 
the connection should always be made under the 
supervision of the city engineer, or other person in 
charge of the public sewers. 




Fig. 3. 



The private sewer should enter the main sewer 
obliquely, so that the inflowing sewage would be 
projected in the same direction as the flow of sew- 
age in the main sewer, as shown in figure 3. A 
square connection would tend to an interference 
with the flow of sewage in the main sewer, and to 
the deposition of solid matters therein at that point. 

35 



The Sanitary Sewerage of Buildings. 

If the main sewer is of brick, the connection 
should be through a glazed stoneware, or cement, 
block, built into the sewer, and having an annular 
opening, in the form of a hub, on the outside, for 
the reception of the spigot end of the first length of 
pipe of the private sewer, as shown in figure 4. 




Fig. 4. 



Where the main sewer is of earthenware, the 
connection should be through a "Sanitary T" or TY 
fitting, as shown in figure 3. 

laying and jointing the pipes. 
At, or near to, the connection of the private sewer 
with the main sewer, provision should be made for 
the subsequent preliminary testing of the sewer, by 
the insertion of a fitting which will permit of the 
plugging of the sewer. For this purpose, where 



36 



Outside Sewers. 

earthenware pipes are used, a "half-socket" pipe, a 
plain pipe and "saddle chairs," or a plain pipe and 
collar, or sleeve, as shown in figures 5, 6 and 7, 
would be necessary. This should' be fitted in its 



Sfe 




Fig. 5. 



place at the same time the other pipes are laid, so 
that the sewer may have butt joints throughout. 

Where iron pipes are used for the sewer, the 
opening for the testing plug may be obtained by the 




Fig. 6. 

use of an inspection piece, similar to that shown in 
figure 8. This would be caulked in place when the 
sewer is laid, and such a fitting at this point might, 

37 



The Sanitary Sewerage of Buildings. 

at some future time, be of service in the removal of 
stoppages, or the cleansing of the sewer. 

In laying the sewer pipes, it is important that 
they have an even bearing throughout their entire 
length, and nut, as is usual, rest simply upon their 
hubs. This can be accomplished by making a hol- 
low place under each hub, as shown in figure 9, and 
will serve the further purpose of giving plenty of 
room to make good joints. 




Fig. 7. 



Where the pipes are supported by the hubs alone, 
it is impossible to properly tamp the earth solid 
under them, and for this reason they would be 
liable to fracture by the careless filling in of the 
trench, or by the weight of the superincumbent 
earth. 

In making the joints of earthenware sewers, it is 
essential that a gasket of oakum precede the ce- 
ment, and for the following reasons : 



38 



Outside Sewers. 

Where oakum is not used, each pipe must be ce- 
mented, and the inside of the joint examined to see 
that no cement remains on the inside, before another 
pipe can be laid; and in placing the next pipe in 
position, the joint last made would be disturbed, 
and the cement forced out of its place, and possibly 
into the sewer. Further, pipes laid one at a time 
cannot be laid in as true a line as where a number 
of them are laid and adjusted prior to the jointing. 







$/MiM»WMMMMM»JJW»/»»Wl«MJ2WM»#M»MX**3^ 



&SQ 



Fig. 8. 

Not being provided with rims, in the absence of 
the gasket of oakum, the spigot ends of the pipes 
would tend to settle in the joints, and leave a large 
space at the top, and little or no space for cement 
at the bottom, as shown in figure 10. 

For the joints of earthenware pipes, nothing but 
the best grades of Portland cement, and clean, 
sharp sand, in the proportion of one measure of 
cement to one of sand, should be used, the mixture 
being tempered with water until it is of the con- 
sistency of thick mortar. Cement which has begun 

39 



The Sanitary Sewerage of Buildings. 

to harden before it could be used should not be 
worked over or mixed with new material. 

In pioperly constructed earthenware pipes, the 
glazing will be omitted from the insides of the hubs, 
and from the spigot ends for a distance equal to the 
depth of tne hubs. It has been stated that the lack 
of glazing at these points will render the pipes por- 
ous, but if the cement covers every portion of the 
unglazed surfaces, it will be impossible for any 




Fig. 9. 

liquid, inside or outside of the sewer, to affect the 
pipes at these points, and the cement will adhere 
more firmly to such pipes than to those having 
glazed surfaces at the joints. 

In making the joints of iron pipes, the hubs 
should be filled to one-third of their depth with 
oakum, well and evenly calked, and the remaining 
spaces, and to a depth of one-eighth of an inch 
above the hubs, with molten lead, which should also 
be well and evenly calked. If the filling and ca'lk- 



40 



Outside Sewers. 

ing have been properly carried out, the lead will 
remain flush with the tops of the joints when fin- 
ished. 

THE MAIN TRAP. 

The utility, or otherwise, of the main trap in the 
sewerage of buildings has, for more than a decade, 
been the subject of much controversy, and has re- 
cently received much attention at the hands of many 
prominent sanitarians. For the proper considera- 
tion of this question, it will be necessary to review 
and analyze, at some length, the principal objections 



v/s/ss//////s//;s//s///s/a 



V/WSSSSS/S/SS/sV////^ 




<s///,»»»,»S»/S/»» 



w;/m,/mm/;m/mm 



which have been raised against the use of these 
traps, and the benefits which it is claimed would be 
secured by their discontinuance. 

The principal objections raised against the use of 
main traps may be summarized as follows : 

i. That they interfere with the rapid flow of 
sewage from the private sewers. 

2. That thev are filth and o-rease holders. 



41 



The Sanitary Sewerage of Buildings. 

3. That stoppages in them are of frequent occur- 
rence. 

4. That foul odors are generated in them to 
such an extent as to render them a nuisance, or a 
danger to health, when a portion of the air which 
has been in contact with them is forced out of the 
air inlet. 

5. That the water in them is liable to be frozen 
by the currents of cold air passing over them. 

6. That their water seals are liable to be de- 
stroyed by syphonage or pressure. 

7. That they necessitate the provision of an oth- 
erwise useless and objectionable appurtenance, the 
air inlet. 

8. That if the air inlet becomes oostructed, an 
air locked condition may prevail in the pipes be- 
tween the traps of fixtures and the mam trap. 

9. That they tend to accelerate the syphonage of 
iraps located in the lower stories of a building. 

10. That they prevent air circulation in those 
portions of the sewers between them and the public 
sewers. 

Benefits claimed to be derived from the discon- 
tinuance of main traps : 

1. That the main sewers, and every portion of 
the private sewers, will be well ventilated by the ex- 
tensions of the soil, waste and re-vent pioes above 
the roofs of buildings. 



42 



Outside Sewers. 

2. That the clogging, by frost, of the tops of 
soil, waste and re-vent pipes, above the roofs, will 
be less likely to occur where warm air from the pub- 
lic sewers is constantly passing up them than with 
the sluggish movement of air incident to the use of 
the main trap. 

Analyzing the several objections, it is found that, 
with the exception of those objections numbered 
seven and ten, and possibly number one, the objec- 
tions are not valid, and that the objectionable feat- 
ures mentioned are due rather to the use of im- 
properly constructed traps, or to improper or im- 
perfect installation of the traps and accessories. 

That the sewage flowing through a private sewer 
will not, ordinarily, meet with any resistance, save 
that of friction, until it reaches the main trap, is 
conceded, but if the fall of the sewer near to and on 
the "house" side of the trap is increased slightly, 
and the bore of the inlet side of the trap is con- 
tracted so that it is slightly less than the sewer, or, 
better still, if the trap is constructed as shown in 
figure ii, the sewage will pass through quickly and 
leave the trap clean. 

It is safe to say that any ordinary sewage will 
pass through a properly constructed main trap, and 
that if a stoppage should take place in such a trap, 
it would be due to an article, or articles, of a bulky 
or heavy nature which might, by accident or design, 
gain access to the sewers. 

43 



The Sanitary Sewerage of Buildings. 

If, then, it is possible to render a main trap self- 
cleansing, the objection relative to foul and danger- 
ous odors from them, escaping at the air inlets, is 
removed. 

The water in a main trap will not be likely to 
freeze if the trap is below the frost line, and ar- 

o 




Fig. 11. 

ranged as shown in figure n. Where this trap is 
inside the building, the air inlet should be arranged 
as shown in figure 12. It will be seen that, in 
either case, the inflowing cold air cannot materially 
affect the temperature of the water in the trap. 



44 



Outside Sewers. 

The possibility of the water seal of a properly 
constructed main trap being destroyed by syphon- 
age or pressure is very remote; and if this should 
take place, the seal would soon be restored, and any 
sewer air which might pass into the house pipes 
would be discharged, from the extensions of the soil 
and other pipes, at a safe point above the roof. 




Fig. 12. . 

That the main trap necessitates the provision of 
an objectionable appurtenance — the air inlet — is 
well known to anyone who has had to do with their 
location, especially where the main trap is in close 
proximity to a public thoroughfare. There are, 
however, very many instances in which a suitable 
location for the air inlet can be found, in many 
cases by the extension of the same for some dis- 



45 



The Sanitary Sewerage of Buildings. 

tance, horizontally, from the inspection shaft of the 
main trap. 

If the air inlet is properly located and constructed, 
the possibility of a stoppage in the same, with the 
consequent air lock in the sewer between the house 
fixtures and the main trap, is very remote. 

From our present knowledge of the conditions 
under which the syphonage of traps occurs, the 
statement that a main trap will tend to accelerate 
the syphonage of traps located in the lower stories 
of a building, does not appear to have foundation, 
assuming, of course, that the construction of the 
trap does not seriously retard the flow of sew- 
age, and that a proper air inlet is provided. 

From the standpoint of the individual house 
owner, the statement that the ventilation of that 
portion of the private sewer between the building 
and the main sewer is, by the interposition of a 
trap, rendered impossible, is really the most logical 
argument which has been advanced in opposition 
to such a practice, and yet, in many instances, the 
length of sewer which would thus be left without 
ventilation would be very small. 

From the standpoint of the general public, the 
trapping of the public sewers by openings at the 
grade, especially in narrow streets and congested 
localities, is objectionable, and may become a source 
of danger to the passer-by and to those residing in 
the immediate vicinity of such openings. On the 



46 



Outside Sewers. 

other hand, if the main trap was omitted from each 
house sewer in a locality, and every such sewer was 
ventilated by a pipe extended above the roof of a 
building, the sewer openings in the streets would 
usually act as inlets for air, and the foul air in the 
public sewers would be discharged above the roofs 
of the buildings. Further, the more rapid circula- 
tion of air in the public sewers, which would thus 
be secured, would prevent the accumulation of foul 
air in any part of the sewerage system ; and the 
temporary discharge of air from the public sewers, 
at a grade opening, would be much less objection- 
able than under the plan in general use at the pres- 
ent time. 

There is, however, an objection to such a method 
of ventilating the public sewers, in fact, if a defect 
should occur in the house pipes, a trap become un- 
sealed, or any pipe or fixtures be disconnected for 
repairs or alterations, foul air from the main sewers 
would gain access to the building. 

At the present time, there are very many public 
sewers which are sewers of deposit, and which 
make their presence known to the olfactory organs 
of those passing by a sewer ventilator or an un- 
trapped catch-basin in a very unmistakable man- 
ner. It is scarcely necessary to state that the en- 
trance to a dwelling of a very small volume of air 
from such a source would be very objectionable 
from aesthetic and hygienic standpoints. 



47 



The Sanitary Sewerage of Buildings. 

With many others, I believe that every trap in a 
system of house sewerage is a necessary evil, and 
would gladly welcome any change which would do 
away with them, together with their usually com- 
plicated re- vents; but so long as the unwholesome 
or dangerous character of sewer air is recognized — 
and our elaborate system of regulation of plumbing 




Pig. 13. 

work is evidence of this view — so long must we put 
up the barriers, and there is nothing yet discovered 
so effectual for this purpose as the water seal. 

In order to secure the ventilation of the greater 
portion of the outside sewer, together with a better 
flushing of the sewer and the location of the air 
inlet at a desirable distance from the building, the 
main trap should, ordinarily, be located as near to 



48 



Outside Sewers. 

the main sewer as practicable, and be surmounted 
by a manhole to facilitate inspection and cleansing, 
upon which points more will be said under the head- 
ings, "The Fresh Air Inlet" and "Accessibility." 




Fig. 14. 

A good arrangement of the main trap and man- 
hole is shown in Figs. 13, 14 and 15. It will be 
seen that the trap is located out of the way of the 
inflowing cold air and yet is accessible from the 
manhole. 

It will be seen that the trap is located out of the 
way of the inflowing cold air and yet is accessible 
from the manhole. 

In the absence of a manhole at the main trap it is 
suggested that the construction and arrangement 
of the trap and accessories be in accordance with 

49 



The Sanitary Sewerage of Buildings. 

the plan shown in Fig. n, which consists of an ordi- 
nary P trap, and into the hub of which is placed a 
T fitting. Where the amount of fall is limited, so 
that the difference between the levels of the sewer 
on either side of the main trap must be slight, the 
T fitting can be cut down until the side hub is nearly 
on a level with the hub of the trap. Sufficient pipe 




Fig. 15. 

should be added to this fitting to reach to within 
six inches of the surface of the ground, and a brick 
or cement box constructed around the pipe and fin- 
ished level with the surface, the whole being sur- 
mounted by a flat stone, or a metal plate, to keep 
out solid matters and provide for easy access to the 
trap. The trap should have a moderately deep seal 
and be set level. 



50 



Outside Sewers. 

the fresh air inlet. 

The location of the air inlet will often tax the in- 
genuity of the plumber, and will require different 
treatment in nearly every instance, so that a univer- 
sal plan cannot be laid down. 

The top of a manhole should not be left open for 
the admission of air to the sewer because of the 
danger of freezing of the water in the trap, and for 
the further reason that dirt and other solid mat- 
ters might thus gain access to the sewer. 

The continuation of the inspection shaft of a 
main trap above grade for the air inlet is not desira- 
ble, because it would render the inspection and 
cleansing of the trap difficult. The arrangement 
of main traps shown in Figs, n and 12 may be car- 
ried out, with slight modifications, in nearly every 
instance. 

To be effective in winter, the air inlet should be 
continued above the grade to a sufficient height to 
prevent the opening being blocked with snow. 

The air inlet should never be placed near to a 
door or window, or to the fresh-air inlet of the 
ventilating apparatus of a dwelling, but should be 
at least fifteen feet distant from all such openings. 

Where the main trap is adjacent to a street, and 
there is a space between the sidewalk and the curb- 
ing of the street, the air inlet may be connected with 
a hollow iron post, placed near to the curb, and 
having openings in the side and near to the top. 



51 



The Sanitary Sewerage of Buildings. 

The addition of an iron ring will convert the same 
into a convenient hitching post. 

Where the air inlet can be located in a lawn, or 
garden, the extension above the ground may be 
concealed, and at the same time protected against 
fracture, by surrounding it with large stones, in the 
form of a rockery, over which vines can be trained, 
and an unsightly object be thus converted into a 
thing of beauty. 

Where the public sewer is in the rear of a build- 
ing ,it is sometimes possible and convenient to ex- 
tend the air inlet above the guter of a low build- 
ing, provided, of course, there are no windows 
in the immediate vicinity of the pipe ; or if the 
main trap is near to a blank wall, the air inlet may 
be carried on the wall to a height of several feet 
above the grade, and concealed if so desired. 

Were all sewers laid in the alleys, as they should 
be, and not in the streets, the location and arrange- 
ment of the main traps and air inlets would be a 
simple proposition, and the discharge of air from 
the sewer openings, or from the air inlets, would 
be much less liable to become an offense to 
passers by. 

ACCESSIBILITY. 

That a sewer, however well constructed, may at 
some time or other become choked, necessitating 
the provision of openings for the removal of such 
stoppages, is well recognized. 



52 



Outside Sewers. 

The provision of access openings to the outside 
sewer is of considerable importance because, in the 
absence of such openings, if a stoppage should oc- 
cur in that part of the sewer it would be necessary 
to do considerable excavating and to break into 
and afterwards repair the sewer. 

Where there is a manhole, constructed as in Figs. 
13, 14 and 15, the passing of cleaning rods and 
tools through every part of the sewer would not 
be difficult. 

Where there is no manhole, and the main trap is 
near to the main sewer, the greater portion of the 
sewer may be cleansed by the insertion of the clean- 
ing tools at the usual access opening at the highest 
point of the horizontal sewer, and the removal of 
the solid matter at the main trap. 

REMOVAL OF SUBSOIL, SURFACE AND ROOF WATER. 

Wherever possible, the water from the subsoil 
drains, yards, areas and cellar floors should be dis- 
charged on the surface of the ground, into a natural 
water course, or into land drains, and not into a 
sewer ; but where this is not practicable, there should 
be but one connection with the sewer, and that 
through a trap, with a deep seal, placed near to 
and on the "house side" of the main trap, prefer- 
ably in the wall of the manhole (if any), from which 
the trap could be easily reached for the purpose of 
inspection and cleansing. As the seal of this trap 
will be liable to become weakened, or broken, during 



53 



The Sanitary Sewerage of Buildings. 

a dry spell, provision should be made for keeping 
the trap constantly supplied with water by the dis- 
charge into the drain leading to the trap of some 
fixture which receives comparatively clean water at 
frequent intervals. The drip pipe from a refrigera- 
tor would answer the purpose, but should not have 
direct connection with the drain or trap. 

Where the main sewer is small, and there is 
danger of sewage backing up into the private sewer 
during heavy rains, the subsoil and cellar drains 
should not be connected with the sewer, but dis- 
charge into a well, outside the building, from which 
the water could be removed by hand, or by means 
of a pump. This well should not be in close prox- 
imity to a building because foul odors may be given 
off from the stagnant water, even when at rest, and 
would be certain to occur when the same was being 
removed. 

Where the rainfall is to be admitted to the sewer 
the connection should usually be through the same 
trap which receives the subsoil and surface water, 
but care should be exercised in making this connec- 
tion so that flooding of the subsoil may not take 
place during heavy rains. 



54 



CHAPTER III. 

Inside Sewers. 

11J EAVY cast iron pipes, having weights corres- 
ponding to those shown in Table 2, are the 
only materials considered to be suitable and safe for 
the sewers on the inside of a building and for a dis- 
tance of at least three feet outside the foundation 
walls. Earthenware pipes are not considered safe 
for this purpose because of their liability to be broken 
by the settling of the walls of buildings under which 
they would have to pass. Where the acid wastes of a 
laboratory, or any sewage containing strong acids in 
sufficient amount to injure an iron sewer, are to be 
removed it would be necessary to make use of earth- 
enware pipes, in which case only the best quality of 
pipes should be used, and, when laid and jointed, 
should be encased in a substantial ring of cement 
concrete, and relieving arches built over each open- 
ing in the walls through which the pipes may have 
to pass. The latter precaution might be observed 
with advantage where the sewer is constructed of 
extra heavy cast iron pipes, particularly in the case 
of buildings of considerable height and in new 
buildings which have not got through settling. 

55 



The Sanitary Sewerage of Buildings. 

size and inclination. 

The size and inclination will be governed largely 
by the size and inclination of the outside portion of 
the sewer, the methods of determination of which 
are explained in Chapter II. A size of less than 
four inches is not desirable, and a four-inch sewer 
will be large enough for the inside sewer of any 
ordinary building. 

UNDERGROUND VS. HANGING PIPES. 

Wherever possible the laying of a sewer under 
the basement floor of a building should be avoided 
and the soil and waste pipes run on the walls or ceil- 
ings of the basement to the point where the sewer 
enters the building. Where the sewer must be 
laid under the floors care should be taken not to 
place the same in or under any room to be used for 
the storage of coal, or any other heavy or bulky 
substance, or in any other position where it would 
not be easy to reach the sewer in the event of 
necessary alterations or repairs. 

No part of a sewer should be placed in or under 
a plenum chamber, or other place set apart for the 
fresh-air room of the ventilating apparatus of a 
building, because in the event of a leak, or the dis- 
connection of any pipes for alterations or repairs, 
the air supply of the building would be contami- 
nated. 



56 



Inside Sewers. 

connection with the outside sewer. 

Where the sewer outside the building is of earth- 
enware considerable care must be exercised in mak- 
ing the connection between the earthenware and 
iron pipes to avoid leakage or stoppages at this 
point. 

Where the metal and earthenware pipes have not 
the same internal diameter, a reducer should al- 
ways be used, and the joint made with oakum and 
cement in the manner previously described for the 
jointing of earthenware pipes with those of the 
same material. 

ACCESSIBILITY. 

Access openings should be constructed at the 
end of each main or branch sewer, at every change 



Fig. 16. 

in the direction of the sewers, and at such other 
points as may be necessary to enable the whole of 
the sewers to be cleaned out in the event of stop- 
pages. 

In the construction of the cleanouts at the ends 
of the sewers, bends of large radii, only, should 



57 



The Sanitary Sewerage of Buildings. 

be used. Square bends are not permissible be- 
cause they would interfere with the passage of 
cleaning rods into the sewer. 

Where it is necessary, or desirable, to conceal 
the clean out plugs, they may be arranged as in 
Figure 16, and such an arrangement at the end of 
a sewer would render the insertion of cleaning rods 
more easy than where the plug is brought up 
square with the floor. 

FLOOR DRAINAGE. 

By reason of their liability to become choked 
with coal dust, ashes, dirt, or other refuse, com- 
monly found in basement rooms, and for the fur- 
ther reason that the water seals of traps in such 
locations soon become broken by evaporation, floor 
drains should not be permitted in any basement 
room other than that used for laundry purposes. 

For the reasons mentioned in the preceding 
paragraph, in the construction of the floor drain 
it will be necessary to make provision for keeping 
solid matters out of the sewer, and for the main- 
tenance of the seal of the trap. The common 
practice of using a "Bell" trap (Figures 17, 18 
and 19), by itself or in conjunction with any other 
trap, for this purpose cannot be too strongly con- 
demned, and for the following reasons : 

The "well" of the trap and the small hole in the 
strainer soon become filled with solid matters, to 



58 



Inside Sewers. 

remove which the strainer must be lifted and with 
it the "Bell" which constitutes the dip of the trap, 
and when this occurs the seal of the trap is broken. 
Even when the trap is clean, the flow of water 
through it is very slow, and for this reason, when a 
considerable amount of water is to be removed, 




Fig. 17. 

the strainer is usually taken off, and quite fre- 
quently left off for a considerable period of time. 

The strainer being light is easily broken, and a 
broken strainer usually means a broken seal. 

The seal of the trap is very shallow and there- 
fore easily broken by evaporation or siphonage. 



59 



The Sanitary Sewerage of Buildings. 

When placed on the top of another trap, as is 
frequently done, an air lock is formed between the 
traps, and the usual sluggish flow of water through 
traps of this kind is rendered still more inert, neces- 
sitating the removal of the strainer, with the re- 
sults before mentioned. 




Fig. 18. 

A combination catch-basin and trap, for the re- 
moval of surface water not only from basements, 
but also from yards, areas, public toilet rooms, 
slaughter houses, stables, and many business and 
manufacturing establishments where washing of 
the floors is necessary, is shown in Figure 20. The 
catch-basin should be constructed of cement, pref- 



60 



Inside Sewers. 

erably circular in cross section and rounded at the 
bottom to facilitate cleansing. The outlet should 
be a square elbow, with inspection hole and cover. 

ARRANGEMENTS FOR FLUSHING. 

In order to carry out the principle of simplicity 
in the construction of sewers, every possible effort 




Fig. 19. 

should be made to obtain a sufficient amount of fall 
to render the sewers self-cleansing, and obviate the 
use of complicated and expensive apparatus for 
flushing the sewers. But where the fall must 
necessarily be limited, provision should be made 



61 



The Sanitary Sewerage of Buildings. 

for flushing the sewer at regular and frequent in- 
tervals. This can be best accomplished by the sud- 
den liberation of large quantities of water into the 
sewer at or near to the highest part of the same. 

The frequency with which a sewer should be 
flushed will depend largely upon the inclination 
of the sewer and the number of closets discharg- 
ing into it. In many instances a daily flushing will 




Fig. 20 



be all that is necessary to keep the sewer free from 
accumulations of solid matters. 

The flushing tank should be located in the base- 
ment, preferably in a small room constructed or 
set apart for that purpose, and the outlet of the 
tank properly trapped to prevent the passage of 
sewer air into the basement during the time the 
tank may be empty. 



62 



Inside Sewers. 

There are many different forms of flushing tanks 
and apparatus on the market, but, by reason of its 
freedom from working parts and comparatively 
noiseless action, preference should be given to the 
siphon tank, such as is used in the flushing of the 
various forms of trough closets. 

The capacity of the flushing tank will depend 
largely upon the size and length of the sewer, a 
large or long sewer requiring a more powerful 
flush that a smaller or shorter sewer. 

By experiment it has been found that a velocity 
of four and one-half feet per second will remove 
any of the solids likely to find their way into a 
sewer, and a tank for the flushing of a sewer 
should be capable of producing this, or even a 
greater, velocity, and of discharging its contents 
in the space of one minute, or even less. By 
reference to Table 4, in the preceding chapter, it 
will be seen that a four-inch sewer, laid at an in- 
clination which will give a velocity of four and 
one-half feet per second, and running full, will 
discharge approximately 176 gallons per minute, 
and a six-inch sewer, with the proper inclination, 
275 gallons per minute. From this it will be seen 
that for a four-inch sewer a tank holding 200 gal- 
lons (27 cubic feet), and for a six-inch sewer a 
tank holding 300 gallons (40 cubic feet), will pro- 
duce, in each case, a flushing effect considerably 



63 



The Sanitary Sewerage of Buildings. 

greater than what could be obtained by any ordi- 
nary flow of sewage in the sewers. 

Where water is plentiful, the flushing tank 
should be filled from the water mains, but where 
this would be an objection, the waste water from 
wash basins or bath tubs may be discharged into 
the tank, and a sufficient amount of water from 
the mains added, if necessary, to cause the dis- 
charge of the tank to take place at the proper time. 
The use of waste water for this purpose would 
necessitate frequent cleansing of the flushing tank 
to prevent offensive odors from the accumulation 
or organic matters on the sides of the tank. 

Where the rainfall is not stored in cisterns, the 
whole or a portion of the same may be diverted 
into the flushing tank and made to assist in the 
flushing process. 

As the sewer would probably be completely filled 
during the discharge of the flushing rank, and the 
unusual flow exert a powerful influence upon the 
traps of fixtures in the lower part of the building, 
special precautions should be taken to prevent 
the siphonage of such traps by this means. 

Whatever the method of flushing adopted, the 
entire apparatus should be automatic in its action, 
and so located and arranged that it will not be 
liable to freeze, or become a source of annoyance 
or danger to the occupants of the building. 



64 



Inside Sewers. 

cistern waste and overflow. 

Where the rainwater is to be stored in a cistern 
in the basement of the building, whenever practic- 
able, the waste and overflow of the cistern should 
be connected with a drain and not with a sewer. 
Where this is not practicable, the connection with 
the sewer should be through a trap which is con- 
stantly supplied with water, otherwise the over- 
flow would be liable to act as a sewer ventilator 
during a considerable portion of the time. 



65 



CHAPTER IV. 

Soil, Waste and Vent Pipes. 

locations. 

'T 1 HE location of the vertical soil and waste pipes 
will be governed largely by the location of the 
plumbing fixtures, and the proper location of the 
fixtures will obviate the use of long horizontal 
runs, or a multiplicity of vertical stacks. For these 
reasons, the fixtures on each floor should be 
grouped, and be as near to each other as practic- 
able; and the fixtures on different floors, especially 
those of the same kind, should be as nearly over 
each other, vertically, as possible. 

For the purpose of securing a good upward draft 
in the vertical soil, waste and vent pipes, whenever 
possible, they should be on or in inside walls. They 
should not, however, be located in smoke or vent 
flues, as is frequently done, because they would 
not be accessible for repairs or alterations. 

MATERIALS. 

For the construction of the vertical soil and 
waste pipes, and for all vent pipes of two inches 
diameter and upwards, extra heavy cast iron pipes, 
or standard lap welded galvanized or "rustless" 
wrought iron pipes, of the weights shown in Tables 



66 



Soil, Waste and Vent Pipes. 

2, 3 and 7, should be used, but cast iron pipes should 
not be used for stacks of more than one hundred 
feet in height. 

For the branch and vent pipes of less than two 
inches diameter, standard lap welded galvanized or 
"rustless" wrought iron, lead, or brass pipes, of the 
weights shown in Table 7, may be used. 

TABLE 7. 

Weights, in pounds, per lineal foot, of small branch and 
vent pipes. 

Size of pipe. Wrought iron. Lead. Brass. 



1% 




2.5 


1.09 


1% 


2.68 


3.5 


1.32 


2 


3.61 


4.0 


1.79 



In some localities, the use of light weight cast 
iron pipes, known as "Standard," for soil, waste 
and vent pipes, is permitted, while in other locali- 
ties, its use is limited to the extensions to the roofs 
of stacks of more than forty feet in height. It 
should be stated, however, that the most up-to-date 
plumbing codes do not permit of the use of such 
light weight- cast iron pipes for any part of the 
construction of a sewerage system, nor can the 
same be considered suitable for this purpose where 
strength and durability are desired. 

The use of lead pipe will usually be limited to 
the short wastes of bath tubs and to the connec- 
tions of the traps of fixtures, generally, with the 
iron soil, waste or vent pipes. 



67 



The Sanitary Sewerage of Buildings. 

The use of brass pipe will usually be limited to 
the short wastes and vents of wash basins and 
other fixtures where the trap and a portion of the 
waste are exposed to view. As these parts will be 
furnished with the fixtures, in the absence of a 
guarantee from the makers, the quality and prob- 
able durability of the brass tubing will be a mat- 
ter of conjecture on the part of the purchaser. 

Certain makes of brass tubing will split, appar- 
ently without cause, and in using this material in 
the construction of soil, waste or vent pipes, only 
the best annealed pipes should be used. 

Many reasons have been advanced for this defect 
in brass tubing, among which may be mentioned 
the following: 

A lack of or improper annealing of the tubing. 

Hardness of the tubing. 

Lightness of the tubing. 

Detrimental effect of the pickling process prior 
to nickel plating of the tubing. 

Galvanic action, induced by sudden changes of 
heat and cold, or by the passage through the tubing 
of acid or alkaline solutions, particularly where 
they pass through in alteration. By this action, 
the metallic particles of which the tubing is com- 
posed, and which, originally, had crystallized in 
one direction and were parallel with supposed lines 
of force, are caused to change their relative posi- 



68 



Soil, Waste and Vent Pipes. 

tions, and becoming perpendicular to said lines 
weaken the tubing and render it liable to rupture. 

sizes. 

The proper minimum sizes for soil, waste and 
vent pipes are as follows: 

Soil pipes, four inches; waste pipes for slop 
sinks, three inches ; vertical waste pipe stacks for 
baths and wash basins, two inches ; vertical stacks 
for re-venting of traps, two inches. Larger sizes 
than these will not be necessary for any ordinary 
sized dwelling or other building having a corre- 
sponding number of fixtures; and for office build- 
ings, apartment houses, tenements, and other build- 
ings, where the toilet rooms would be connected 
with several stacks, the sizes of the soil and waste 
pipes need not, usually, be larger than five and 
three inches, respectively. For exceptionally large 
buildings of this class, particularly where many 
toilet rooms are placed above each other in a ver- 
tical line, the soil and waste pipes may have to be 
larger than these sizes. 

There is really no scientific basis by which to 
determine the proper sizes of the soil and waste 
pipes, and recourse must be had to empirical rules. 
Such calculations, however, will be subject to wide 
variations, as will be shown later, and will be gov- 
erned entirely by the class and number of fixtures 



69 



The Sanitary Sewerage of Buildings. 

on a particular stack, and the number of times the 
fixtures will be used during a given time. 

With the exception of those instances in which 
the usual rules relative to the minimum sizes of soil 
and waste pipes must be observed, the combined 
areas of these pipes will not, ordinarily, require to 
be greater than the area of the main horizontal 
sewer with which they may be directly connected. 

The cross sectional areas of pipes of the sizes 
which might be required for the construction of 
the soil, waste or vent pipes of a building are 
shown in Table 8. 

TABLE 8. 
Diameter, in inches. Area, in square inches. 

1% 1,227 

iy 2 1,767 

2 3,142 

3 7,069 

4 12,566 

5 19,635 

6 28,274 

7 38,485 

8 50,266 

9 63,617 

10 78,540 

12 113,098 

By reference to Table 4, Chapter 2, it will be 
seen that a four-inch sewer, laid with the proper in- 
clination to furnish a velocity of four and one-half 
feet per second, and running full, will remove, ap- 
proximately, 176 gallons of sewage per minute. 
Upon the basis of a discharge from a water closet 
of four gallons of water in ten seconds of time, a 



70 



Soil, Waste and Vent Pipes. 

four-inch sewer, or its equivalent in vertical stack, 
would take care of the combined and simultaneous 
discharges of seven water closets. As probably 
not more than one-third of the closets in a build- 
ing would be discharging at any one time, a four- 
inch sewer would take care of twenty or more 
closets. By the same rule, a five-inch sewer would 
take care of the discharges from thirty-three clos- 
ets; a six-inch sewer, fifty closets; a seven-inch 
sewer, seventy closets; an eight-inch sewer, ninety 
closets ; a nine-inch sewer, one hundred and eleven 
closets; a ten-inch sewer, one hundred and thirty- 
eight closets; and a twelve-inch sewer, about two 
hundred closets. If we take as the basis of our 
calculations the simultaneous discharges of but 
one-fourth of the closets in a building, by the fore- 
going rule, a four-inch sewer would take care of 
twenty-eight closets; a five-inch sewer, forty- four 
closets; a six-inch sewer, sixty-eight closets; a 
seven-inch sewer, ninety- two closets; an eight-inch 
sewer, one hundred and sixteen closets ; a nine-inch 
sewer, one hundred and forty-eight closets; a ten- 
inch sewer, one hundred and eighty-four closets, 
and a twelve-inch sewer, two hundred and sixty- 
four closets. It is quite possible that, in actual 
practice, a larger number of closets than those men- 
tioned above could be taken care of by the pipes of 
the sizes given in each case. This would also be 



n 



The Sanitary Sewerage of Buildings. 

the case if the sewers were laid with greater in- 
clinations than those shown in Table 4. For in- 
stance, a four-inch sewer laid with an inclination 
of 1 in 23 will cause a velocity of six feet of sew- 
age per second and will discharge 230 gallons per 
minute, and when laid with an inclination of 1 in 
10.2 will cause a velocity of nine feet per second 
and discharge 346 gallons per minute. Assuming 
that one-fourth of the closets attached to such a 
sewer would be discharged simultaneously, when 
laid with the inclination of 1 in 23 the sewer would 
take care of forty closets, and with a fall of 1 in 
10.2, sixty closets. 

Where the soil pipes receive the combined dis- 
charges from water closets, bath tubs, wash basins, 
sinks, etc., the determination of the sizes of the ver- 
tical stacks will be more difficult than where only 
the water closets are to be considered. In all such 
calculations, the probable maximum amount of 
water which will be discharged by any combina- 
tion of fixtures in a given time will be the only 
basis upon which to determine the sizes of the va- 
rious stacks. 

As illustrating the difficulty which has been ex- 
perienced in making uniform rules to govern the 
sizes of soil pipes, the following extracts from the 

72 



Soil, Waste and Vent Pipes. 

most recent plumbing codes of several of the 
largest cities in this country may be of interest: 

Jersey City. 

Sec. 2. The sizes of vertical lines of main soil pipes will 
be governed by the number of fixtures discharging into 
same. * * * The following sizes must be used: 
For 1 and less than 10 water closets with other 

fixtures 4 inch. 

For 10 and less than 20 5 inch. 

For 20 or more 6 inch. 

New Orleans. 
Sec. 36. Soil pipes are never to be less than 4 inches in 
diameter. If more than four water closets discharge into 
it, the soil pipe must be five inches in diameter, and in 
buildings over 5 stories in height, where more than eight 
closets connect, it shall be 6 inches in diameter. 

St. Paul. 

The diameter of soil pipes must be not less than those 
given in the following table: 

Main soil pipes 4 inches 

Main soil pipes for water closets on five or more 

floors 5 inches 

Rochester, N. Y. 

Soil Pipes. 
Minimum Diameter. *Number of Fixtures. 

4 inches 1-30 

5 inches 30-50 

6 inches 51- 

*1 water closet 2 fixtures 

1 bath, etc 1 fixture 

Toledo. 
Soil pipe reciving waste from six water closets or 
bathrooms shall be four inches in diameter. Soil pipe re- 
ceiving waste from six and not more than ten water clos- 
ets or bathrooms shall be five inches in diameter. Soil 
pipe receiving the waste from more than ten water clos- 
ets or bathrooms shall be six inches in diameter. 



73 



The Sanitary Sewerage of Buildings. 

Philadelphia. 
Vertical lines. Number of water closets. 

4 inches 1 to 6 

5 inches 7 to 12 

6 inches 13 to 20 

Milwaukee. 
The number of water closets allowed on a stack of soil 
pipe above the basement floor will be as follows: Four 
closets on a four-inch soil pipe, ten closets on a five-inch 
pipe, twenty-five closets on a six-inch pipe, and when 
more than twenty-five closets are put in, eignt-inch pipe 
will be required. 

Washington, D. 0. 
Vertical runs. No. of water closets. 

4 inches 1 to 12 

5 inches 13 to 25 

6 inches 25 to 40 

Newark and Paterson, N. J. 

Main soil pipes 4 inches 

Main soil pipes for water closets on five or more 

floors 5 inches 

Main soil pipes for tenement houses or factories 

exceeding three stories 5 inches 

Cleveland and Columbus, Ohio. 

Maximum number of fixtures connected to: 
Size of Soil and waste. Soil pipe alone, 

pipe. Branch. Main. Branch. Main. 

Inches. No. fix. No. fix. No. water clos. No water clos. 

4 48 96 12 24 

5 96 192 24 48 

6 168 336 42 84 

7 280 560 70 140 

8 420 840 105 210 

9 580 1,160 145 290 

10 800 1,600 200 400 

11 1,060 2,120 265 530 

12 1,420 2,840 355 710 

In the above table three feet of urinal trough or wash 
sink, 1 bath basin, sink or smaller fixture counts as 1 
fixture; and 1 water closet, pedestal urinal or slop hopper 
sink counts as two fixtures. 



74 



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BQ 



Soil, Waste and Vent Pipes. 

sizes for vertical waste pipes. 

The same difficulty has been experienced in the 
determination of the proper sizes of the vertical 
waste pipes, as will be seen by the accompanying 
summary of the sizes specified in the plumbing codes 
of the cities previously referred to . 

In the several codes the specifications relative 
to the numbers of water closets or other fixtures 
which may be connected with the branch pipes are 
usually one-half the numbers of those which may 
be connected with the vertical mains of correspond- 
ing sizes. 

In making an estimate of the number of fixtures 
which may properly be connected with any soil or 
waste pipe it should be remembered that in a 
horizontal sewer the velocity of the sewage due 
to gravity will be increased very considerably by 
the force of the falling bodies of water in the ver- 
tical stacks connected with it. In a very high build- 
ing, with the simultaneous discharge of several fix- 
tures on any stack, especially where they are lo- 
cated on the same floor, this would be an impor- 
tant item to be reckoned with, and yet, in the ab- 
sence of definite information relative to the height 
of such columns of water and the distances through 
which they might fall, no reliable estimates could 
be made of their effect upon the normal flow of 
sewage in the horizontal sewer. 



75 



The Sanitary Sewerage of Buildings. 

Another item of more than ordinary importance 
which should be considered in determining the 
sizes of the vertical soil and waste pipes is the pos- 
sibility of siphonage of the traps of fixtures by the 
effect of the falling bodies of water in such pipes. 

Where the quantity of water falling in a vertical 
pipe would be sufficient to completely fill it, and 
thus form a plug, its effect upon the water seals 
of the traps of fixtures on such a pipe would be 
considerable, and might, under certain conditions, 
unseal one or more of the traps. For this reason it 
would be wise to make both vertical and branch 
soil and waste pipes slightly larger than what would 
ordinarily be considered sufficient to properly take 
care of the discharges from the fixtures connected 
with them. More will be said upon this point, and 
also upon the subject of the proper sizes and ar- 
rangements of the vent and revent pipes, in a sub- 
sequent chapter on the siphonage and reventing of 
traps. 

EXTENSIONS TO AND ABOVE THE ROOF. 

Soil, waste and vent pipes should, ordinarily, be 
extended, undiminished in size, to the roof, and in- 
creased by one size before they pass through the 
roof, as shown in Fig. 22, but in no case should any 
extension above the roof be of less diameter than 
four inches. The object of the enlargements is to 
prevent the openings at the tops of the pipes from 



76 



Soil, Waste and Vent Pipes. 

being reduced in size by frost to such an extent as 
to interfere with proper ventilation. 




Fig. 22. 

The combined areas of the vertical soil and waste 
pipes which are to be continued above the roof — 
measured below the enlargements under the roof — 
should in no case be less than the area of the main 



77 



The Sanitary Sewerage of Buildings. 

sewer of the building, and one of them should be 
connected with the sewer at or near its highest point, 
and have the same diameter as the sewer at that 
point. The areas of the several pipes may be found 
in Table 8 in this chapter. 

Where two soil or waste pipes, or one soil and one 
waste pipe are not more than say twenty feet apart, 
and any of them, by itself or in combination with 
other vertical stacks extended above the roof, is of 
sufficient size and properly located for the efficient 
ventilation of the sewer, the two pipes may often be 
connected with each other above the highest fixture 
and pass through the roof as one stack. In carrying 
the one extension over to the other — which would 
usually be done in the attic — wherever possible, two 
45° elbows and an inverted Y fitting should be used, 
so as to give the pipes a good upward incline, as 
shown in Fig. 22, and the inclined pipes should be 
well supported throughout their entire length. The 
arrangement is applicable also to the vertical exten- 
sions of branch soil or waste pipes which are not 
more than twenty feet from the main stacks. 
Where the area of the extension which is to be 
continued through and above the roof would not 
be large enough for the proper venting of both 
pipes, the connection should be made above the 
increasor, in which case the latter should be placed 
at a point lower down than is usual, and made 
large enough for the two pipes. 



Soil, Waste and Vent Pipes. 

supports. 
In the construction of the vertical soil and waste 
pipe stacks the provision of proper supports for 
the pipes is of considerable importance, because 




Fig. 23. 



the settlement of a stack, however slight, will prob- 
ably result in a fracture of the sewer at the base 
of the stack. 

The principal support should be at the base of 
the stack, in the form of a substantial brick, ce- 



79 



The Sanitary Sewerage of Buildings. 

ment or stone pier immediately under the stack, 
and yet in very many buildings of not more than 
two or three stories in height this precaution is 
neglected or not deemed necessary. 

Where cast iron pipes are used, in order that the 
stack may have a solid and sufficient bearing upon 




Fig. 24. 



the masonry pier, a special fitting (Fig. 23), in 
the form of an elbow, and known as "heel fitting," 
"heel rest," or "flat foot," should be used at the 
base of the stack. 

In the case of buildings of more than forty feet 
in height, in addition to the support at the base 
of the stack there should be one support in every 
twenty ' feet. Where an offset occurs the pipes 
above the offset should be well supported by a 



80 



Soil, Waste and Vent Pipes. 

special heel fitting, as at the base of the stack. It 
should be remembered, however, that there will De 
considerable expansion and contraction in a long 
stack into which both hot and cold water are dis- 
charged, for which allowance should be made in 
the construction of supports other than those at 
the base of the stack. 

The vertical soil and waste pipes may be held in 
place on the walls by means of bands of wrought 
iron, of suitable width and thickness, fastened to 
wooden blocks in the walls by corkscrew bolts, as 
shown in Fig. 24, but the bands should be loose 
enough to allow of expansion and contraction of 
the pipes. 

Where a soil or waste pipe stack is to be placed 
in a special groove or chase in a wall it may be 
supported and at the same time held in place 
against the wall by iron rests built in the wall on 
each side of the groove, as in Fig. 25, the hub of 
one pipe in every twenty feet of stack being made 
to rest upon one of these supports. 

LATERAL connections. 

With the exception of the short lengths of lead 
pipe connecting the traps of fixtures with the branch 
soil or waste pipes, the latter should be constructed 
of the same materials as the vertical pipes. 



81 



The Sanitary Sewerage of Buildings. 

As previously stated, the sizes of the branch soil 
or waste pipes are usually governed by the sizes of 
the vertical stacks, that is to say, the number of 



Fig. 25. 



fixtures which may be connected with a branch pipe 
is limited to one-half the number which may be 
connected with the vertical stack of corresponding 
size. 



82 



Soil, Waste and Vent Pipes. 

By experiment it has been determined that where 
the branch pipes are not more than three feet in 
length and are made one size larger than the traps 
connected with them, the use of special vent or 
revent pipes will not, usually, be necessary. For 
this reason, it would be well to place the fixtures 
and vertical pipes as near to each other as practica- 
ble. 




Fig. 26. 

The branch pipes should, in every case, be con- 
nected with -the vertical stacks by means of TY or 
Sanitary T fittings, and never with ordinary T 
fittings. An excellent form of fitting for this pur- 
pose, and one which would tend to prevent the 
siphonage of traps by the falling bodies of water in 
the vertical stacks, is shown in Figure 26. 

Where the branch pipes are of considerable 
length, and serve a number of fixtures, they will re- 



83 



The Sanitary Sewerage of Buildings. 

quire to be continued, vertically, to a point above 
the roof, but if the branch pipes are not more than 
twenty feet in length, their extensions may be con- 
nected back into the vertical pipes above the highest 
fixtures. 

As the vertical pipes will expand and contract, 
the branch pipes should be free to rise and fall with 
them. 

Where the appearance of the branch waste pipes 
in a room would not be an objection, they would be 
more accessible if carried to the vertical stacks on 
the walls instead of under the floors. 

Every part of the soil and waste pipes, vertical 
and horizontal, should be in plain sight, but where 
any part must be concealed, the covering in front of 
or over the same should be easily removed. 

Where the vertical stacks are in a straight line 
throughout, and are open at the tops, the provision 
of access openings at the bases of the stacks will 
usually be sufficient for the removal of stoppages. 
The ends of the branch pipes should, in every case, 
be provided with access openings, because stop- 
pages are more likely to occur in them than in the 
vertical pipes. 



84 



CHAPTER V. 

Roughing in Test, and Filling in of the 
Trenches. 

tJAVING completed the construction of the sewei 
and the soil and waste pipes and their branches, 
the next step will be to ascertain the soundness, or 
otherwise, of the materials and workmanship. This 
is called the "roughing in" test, and should be ap- 
plied before any portion of the work has been cov- 
ered in or enclosed. There will be times, however, 
when the underground sewer must be covered in 
before the soil and waste pipes are ready for test- 
ing, in which case a separate test must be made of 
the underground sewer. This test should be very 
thorough, because a weak spot in the pipes or joints 
which might be able to withstand a moderate pres- 
sure at the time of the test would later be very 
liable to cause a leak, and, being underground, this 
would not, usually, be detected from the surface. 

In localities which have plumbing codes, the test- 
ing is usually done under the direct supervision of 
an inspector from the department having jurisdic- 
tion over such work ; in localities which have no 
such official, the testing will usually be neglected, 
unless demanded by the architect or by the owner 
of the building. Reliable tests of this nature often 
require considerable preparation, and mean a loss 



85 



The Sanitary Sewerage of Buildings. 

of time to the person executing the work, but they 
are a powerful incentive to good work, and should 
always be insisted upon by those having super- 
vision of such work. 

There are two methods of testing the roughing in 
work in general use: 

i. The hydrostatic, or water test; and 

2. The pneumatic, or air test. 

The principle in both tests is the same, the pipes 
being subjected to a pressure from within, in the 
first case by water, and in the second, by air. 

In the hydrostatic test, the pipes are filled with 
water, and the pressure is usually obtained by the 
weight of water in the vertical pipes. Where only 
the horizontal pipes are to be tested, and the pres- 
sure of water in the street mains, or other source, 
from which the pipes are to be filled is not equal to 
say twenty-five pounds per square inch, a pressure 
pump will be necessary to make the test. 

The pressure of water, per square inch, in a ver- 
tical pipe will vary considerably, and may be cal- 
culated by multiplying the height of the column of 
water, in feet, by .4327 (the weight of a column 
of water one foot high and having an area of one 
square inch). 

' The pneumatic test is made by forcing air into 
the pipes by means of a test gauge pump, similar to 
that shown in Figure 27. This test is usually ap- 
plied under a pressure of ten pounds -per square 



86 



Roughing in Test. 



inch, which is equal to twenty inches of mercury. 
Spring gauges, similar to that shown in the center 




The Sanitary Sewerage of Buildings. 

of Figure 27, should not be used, because they are 
not as reliable as the mercury gauge, shown on the 
right of the Figure. 

The hydrostatic test is usually preferred to the 
pneumatic test, but it should not be used in very 
tall buildings, because the pressure on the lower 
portions of the pipes would be too great; nor in 
very cold weather, because the water in the pipes, 
or in the oakum packing of the joints, would be 
liable to freeze and burst the pipes ; nor in very 
warm weather when the relative humidity is high, 
because the condensation of moisture on the out- 
side of the pipes would be considerable, and ren- 
der the location of small leaks difficult. 

In making the hydrostatic test, all openings ex- 
cept the tops of the soil, waste and vent pipes will 
require to be securely plugged or sealed, and the 
pipes should be filled at the lowest point so that 
defects may be noted before the pipes are wetted on 
the outside by possible leaks to any considerable 
extent. When the pipes are full, the water should 
remain at the same level for a period of at least 
fifteen minutes. If leaks are detected, the water 
should be lowered below the defective part, and the 
same repaired and re-tested. 

In plugging the pipes for the test, considerable 
care will be required to prevent the plugs being 
forced out and the lower portions of the work 
flooded. Wooden plugs should not be used, be- 



Roughing in Test. 

cause they would have to be driven in to make 
them tight, and jarred loose to get them out, and 
the jarring would be liable to fracture a pipe or 
loosen a joint. Special plugs, of various patterns, 




Fig. 28. 

are made for this purpose, examples of the two 
principal forms of which are shown in Figures 28 
and 29. Wherever possible, the plug shown in 
Figure 28 should be used, but where the plug must 
be placed inside a pipe or fitting, it should extend 



89 



The Sanitary Sewerage of Buildings. 

beyond the hub or it will probably be forced out 
by the pressure of water. 

The ends of lead pipes attached to the branch 
pipes may be securely sealed : 




Fig. 29. 



In small sizes, by pinching together and sol- 
dering over the ends ; and 

In the large sizes, by discs of sheet lead soldered 
into the ends of the pipes. 

In making the pneumatic test, all openings 
should be securely closed, and when the pressure 
has raised the mercury in the gauge to the twenty 



90 



Roughing in Test. 

inch mark it should remain at that level for at 
least fifteen minutes. If leaks occur, there may be 
considerable difficulty in locating them, and, for 




Fig. 30. 



this reason much time would be saved by filling 
the pipes with smoke by means of a smoke-test ma- 
chine, similar to that shown in Figure 30. 



91 



The Sanitary Sewerage of Buildings. 

For an excellent and complete guide to the vari- 
ous methods of testing plumbing work, the reader 
is referred to a recent publication, issued by "Do- 
mestic Engineering," entitled, "Testing Drainage, 
Plumbing and Gas Fitting," by Jno. K. Allen. 

After the underground sewer is tested and made 
good, the filling in of the trench will be in order. 
This work will probably be entrusted to some per- 
son whose knowledge of the strength of sewer 
pipes to resist percussive action is very limited, and 
the careless throwing in of the earth, or the ram- 
ming of a thin layer of earth over the pipes, may 
fracture the pipes at some point, and render the 
sewer insanitary. For this reason, the filling in of 
the first few feet of earth should be done under the 
direct supervision of some person having a special 
knowledge of the requirements of this class of 
work. 



92 



CHAPTER VI. 

Plumbing Fixtures and Accessories. 

TT IS of the first importance that all plumbing fix- 
tures be constructed of impervious and non-ab- 
sorbent materials ; have smooth interiors and pleas- 
ing exteriors ; and be free from hidden or other 
parts which cannot readily be inspected or cleansed. 

The materials which most nearly fulfil the first 
requirement are porcelain, cast iron, steel, copper, 
zinc, tin, lead, soapstone and slate. 

Porcelain is fragile, and therefore not suitable 
for fixtures liable to rough usage, but, by reason 
of the smoothness and durability of its enameled 
surface, is the most popular material for water 
closets, wash bowls, bath tubs and urinals. 

Cast iron is extensively used in the construction 
of kitchen sinks, slop sinks and bath tubs, and for 
water closets which would be subject to rough 
usage or freezing temperatures. Fixtures made of 
this material should be well enameled on the in- 
side, and well painted or enameled on the outside. 

Steel is made use of in the manufacture of kit- 
chen sinks, and for the casings of open copper lined 
bath tubs, and should always be well protected 
against corrosion by a coating of enamel or several 
coats of good paint. 

93 



The Sanitary Sewerage of Buildings. 

Copper is used for the linings of pantry sinks, 
bath tubs, and the finishing tanks of water closets, 
and should always be well tinned on the side which 
will be exposed to the action of water and other 
liquids. 

In the past, zinc was extensively used in the 
manufacture of linings for bath tubs, but these are 
being rapidly superseded by the more sanitary open 
fixtures. 

The use of tin, in sheet form, is confined almost 
exclusively to the linings of pantry sinks, and the 
drip trays and sinks of bars and soda fountains, 
but, by reason of its softness, it requires to be rein- 
forced by wood and is inferior to copper for the 
purposes named. 

Lead is sometimes made use of for the purposes 
mentioned in the preceding paragraph, and also 
for the linings of dish sinks in hotels, restaurants 
and large kitchens. It is also made use of for the 
linings of cisterns for storing water, but should not 
be used for this purpose if the water is soft, or in- 
tended for drinking or culinary purposes. 

Soapstone and slate are used chiefly for laundry 
tubs, and for the stalls of urinals and shower baths, 
and where the best grades of soapstone are used 
and the workmanship is good, fixtures made of this- 
material will possess superior qualities of cleanli- 
ness and extreme durability. 



94 



Plumbing Fixtures and Accessories. 

In view of the fact that modern plumbing fixtures 
are, as a rule, constructed in such a manner that 
wooden casings or enclosures will not be necessary, 
it is scarcely necessary to sound a warning against 
the use of fixtures which require such casings or 
enclosures to give them a finished or pleasing ap- 
pearance. 

CELLAR FIXTURES. 

Plumbing fixtures should not be placed in dark, 
unventilated cellars, nor should they be placed in 
any cellar unless they will be often used and have 
proper attention so as to ensure the requisite seal- 
ing of the traps and the cleanliness of the fixtures. 

Water closets in cellars are especially objection- 
able, but where they are deemed necessary, as in 
schools and other public buildings, the apartments 
in which they are located should have at least one 
outside wall with windows for light and ventilation, 
and the closets should be of porcelain and of the 
siphon pattern. Hopper closets, so frequently made 
use of for the cellars of dwellings and stores, should 
never be used in such locations. 

Sinks are frequently placed in cellars, and, in 
many instances, are not often used, constituting a 
source of danger by the evaporation of the water in 
the traps. 

Laundry tubs are usually placed in cellars, and 
are really the only plumbing fixtures which may be 



95 



The Sanitary Sewerage of Buildings. 

said to belong to the basement stories of buildings, 
but they should not be placed in any part of a cellar 
which has not a smooth and well drained cement 
floor. 

KITCHEN AND PANTRY FIXTURES. 

Kitchen sinks, together with their drainer tops 
and aprons, or splash plates, should be constructed 
of steel or cast iron, preferably in one piece, with 
substantial porcelain finish, and should be supported 
on metal legs or brackets. A movable dish drainer, 
made of wooden slats, is the only woodwork which 
should be used in connection with a kitchen sink. 

Pantry sinks are usually constructed of sheet cop- 
per, and are either oval or rectangular in shape. 
For small sinks, the oval shape is preferable, be- 
cause the sink can b.e made of one piece of metal 
and will not require any support other than the 
flange at the top. Where the sink has a flat bottom, 
the latter will require to be supported by a wooden 
shelf, giving the sink an unsightly appearance, and 
furnishing a place for the possible lodgment of 
water and the creation of an unsanitary condition. 
Pantry sinks are now made of porcelain, and such 
sinks are attractive in appearance and easily 
cleansed, but the washing of fine glassware and 
fragile crockery in them will be attended with much 
greater risk than in copper sinks, and, for this rea- 
son, the latter will probably be given the preference 



96 



Plumbing Fixtures and Accessories. 

until some more suitable material is discovered for 
this purpose. 

Grease interceptors may well be included in the 
class of necessary evils in connection with the sew- 
erage of buildings because, as a rule, they do not 
receive the attention which they require, and, at 
best, are disgusting to the senses of sight and 
smell. They are not considered necessary in ordi- 
nary dwellings, in which the amount of greasy 
water discharged into the sinks would be small, but 
they are considered necessary in connection with 
the sinks of hotels, restaurants and large kitchens, 
where the amount of greasy liquids passing into 
the sinks would be sufficient to form a considerable 
coating of grease in the private sewers. 

The object of a grease interceptor being the im- 
mediate cooling of the greasy water passing into 
it, and the consequent congealing of the grease — 
which being lighter than the water, will rise to the 
surface and form a scum — the interceptor should be 
constructed of such materials and placed in such 
a location as will facilitate this cooling action. 

By reason of the offensive odors given off during 
the process of cleansing, a grease interceptor should 
be located in some place other than the kitchen, as, 
for instance, in some part of a cellar which is cool 
and well ventilated, and which is not used for the 
storage of food or for the fresh-air room of the ven- 
tilating apparatus. 



97 



The Sanitary Sewerage of Buildings. 

The logical place for a grease interceptor would 
be some point outside the building, but it would 
necessarily have to be near to the surface of the 
ground, and consequently liable to freeze up, and 
the cleansing of the same in winter would often 
be very inconvenient, if not difficult. 

Grease interceptors are frequently constructed of 
cast iron, and some of the larger sizes are provided 
with hollow walls, through which water is made to 
circulate, for the purpose of cooling the water in 
the interceptor and assisting in the separation of 
the contained grease. The small cast iron inter- 
ceptors, intended to be placed on the floor under or 
near to a sink, are considered of little value, because, 
when a considerable quantity of hot water is passing 
through them, the iron will partake of the tem- 
perature of the water and tend to prevent the con- 
gealing of the grease in the water and to liquefy 
whatever grease may have accumulated, with the 
result that much of the grease will probably pass 
into the sewer. A serious objection to the use of 
iron for this purpose is the fact that it will corrode 
and render thorough cleansing of the bottom and 
sides of the interceptors difficult, if not impossible. 

A convenient form of grease interceptor, and one 
which can be made to suit the needs of any building 
and which will effectually separate the grease from 
the water before it can reach the outlet, is shown in 
Figure 31. The bottom and sides may be made of 



98 



Plumbing Fixtures and Accessories. 

hard bricks, laid in cement, or of cement and fine 
gravel. In either case, the inside should be well 




iSectcon an A. 3. 



A — 



n 



Plan. 







H-v-- 



is 
Cover- Seal. 

Fig. 31. 



plastered with cement and be left smooth. In the 
ordinary grease interceptor, the inflowing water 
breaks up the accumulated grease and some of it 



99 



The Sanitary Sewerage of Buildings. 

may be carried along with the water into the sewer. 
This may be prevented by the construction of baf- 
fles, as in Figure 31, and the added distance which 
the water will have to travel in passing through the 
interceptor will give the grease a much better op- 
portunity to become chilled and to rise to the sur- 
face before it reaches the outlet end of the inter- 
ceptor. The cover should be of iron, with a frame 
of the same material, and the latter should be bedded 
in cement. A tongue on the underside of the cover 
corresponding with a groove in the frame, and a 
quantity of heavy oil poured into the groove, will 
form a good seal and prevent air from the inter- 
ceptor escaping into the room. A vent pipe should 
be carried from the interceptor to a convenient point 
outside the building for the purpose of preventing 
an air lock between the trap of the sink and the trap 
of the interceptor, and to allow of the escape of foul 
odors and steam. The outlet should be much larger 
than the inlet so that the water in the interceptor 
may not be siphoned out by the formation of a plug 
of water in the outlet. 

Refrigerators will usually require drainage to the 
sewer and this should be accomplished by making 
the waste pipes discharge over well trapped sinks 
or floor drains. Even though well trapped, the 
waste pipe of a refrigerator should never be con- 
nected directly with a waste or soil pipe. 



100 



Plumbing Fixtures and Accessories. 

TOILET rooms. 

Toilet rooms may be divided into two principal 
classes — private and public. 

Private toilet rooms may be said to include all 
such rooms which are not accessible to the general 
public, but the term is intended to apply principally 
to the toilet rooms of private dwellings, hotel suites, 
private offices and stores other than department 
stores. 

The plumbing fixtures which will be considered 
in connection with the private toilet rooms of build- 
ings are water closets, bathtubs, washbasins and 
slop sinks, two or more of which will usually be 
found en suite. 

Water Closets. — To meet the popular demand for 
a fixture which will effectually remove the excreta 
deposited in it and without leaving any trace of the 
same upon any visible portion of the fixture the fol- 
lowing conditions must be complied with : 

The shape of the bowl and the surface area of 
the water in the same must be such that the inside 
of the bowl above the water line will not, ordinarily, 
be soiled when the fixture is used. 

The flush of water must be sufficient to quickly 
and effectually remove excreta and paper from the 
bowl; to scour every portion of the bowl, both 
above and below the water line ; and to fill the bowl 
to the requisite height with clean water after the 
flushing is accomplished. 



101 



The Sanitary Sewerage. of Buildings. 

The development of the water closet in the past 
twenty-five or thirty years from the filthy and com- 
plicated "pan" closet (Fig. 32) to the "siphon" 
closet of the present time — one type of which is 
shown in Fig. 33 — is an interesting study, and a 
brief reference to which may not be considered out 
of place at this time. 




Fig. 32. 'Tan" closet. 

With the advent of the modern sanitarian came 
the pronouncement that the "pan" closet was an 
insanitary fixture, and many new and so-called sani- 
tary fixtures sprang into existence. 

The "valve" closet (Fig. 34) was one of the 
earliest forms designed to take the place of the 
"pan" closet, and it had many good features to 



102 



Plumbing Fixtures and Accessories. 

recommend it, principal among which was the large 
body of water in the bowl, which, being suddenly 
liberated, insured the speedy removal of excreta 
from the premises. It was found, however, that 
the closet and water service valves often £ot out of 




Pig. 33. "Siphon" closet. 

order, necessitating frequent repairs, and that paper 
would lodge between the valve and its seat, allow- 
ing the water to leak out of the bowl. But the 
chief objection to this closet from a sanitary stand- 
point was the fact that, as ordinarily constructed the 
trap must, perforce, be beneath the floor, neces- 



103 



The Sanitary Sewerage of Buildings. 

sitating the removal of the fixture whenever the 
trap became stopped up. 

The "plunger" closet (Fig. 35) was a slight ad- 
vance over the "valve" closet, in that it provided 
for a trap above the floor ; but the plunger, together 
with the space in which it worked, were easily 




Fig. 34. "Valve"' closet. 

fouled, making this type of closet a foul-smelling 
thing. Further, paper would lodge between the 
rubber ring of the plunger and its seat and allow 
the water to leak from the bowl. 

The defects in the "valve" and "plunger" closet 
led to a demand for a fixture devoid of valves, 
plungers or other working parts, and the all earth- 



104 



Plumbing Fixtures and Accessories. 

enware short "hopper" and "washout" types (Figs. 
36 and 37) became popular, and were believed to 
have solved the problem of a simple and sanitary 
fixture. 

It should be stated that prior to this time, by 
reason of the fact that, under the best conditions, 
the flush of water did not prevent the bowl from 
becoming filthy, the long "hopper" closet (Fig. 38) 
had been almost universally condemned. 




Plunger" closet. 



The short "hopper" type of closet was found to 
be defective, in that it did not hold sufficient water 
to prevent fouling of the bowl, and the shape was 
changed to remedy this defect, with the result that, 
ordinarily, a single flush of water was then found 
to be insufficient to completely remove the contents 
of the bowl after use. 



105 



The Sanitary Sewerage of Buildings. 

The "washout" closet was very popular and held 
sway for many years, but its defects soon became 
apparent, chief among which was the fouling of 
the space between the bowl and the trap. The shape 
was changed from a "back-outlet" to a "front-out- 
let," and also to a "side outlet" closet, but at no time 




uig. 36. "Hopper" closet. 

was there a closet of this type on the market which 
was free from the defect before mentioned, and 
they remained filthy to the last, notwithstanding the 
best of care. 

Up to the time when "washout" closets were 
made with ornamental exteriors, water closets of 
all kinds were, as a rule, almost entirely concealed 
from view by wooden enclosures, usually screwed 



106 



Plumbing Fixtures and Accessories. 

together, and an inspection of the floor beneath the 
fixture would often reveal a very filthy condition, 
particularly where it was the custom to throw slops 
into the bowl. 

In passing it should be mentioned that with the 
advent of the ornamental "washout" closet it was 




Fig. 37. "Washout" closet. 

demonstrated that wooden inclosures were unneces- 
sary not only for water closets but for sinks, wash- 
basins and bathtubs, and a complete reformation in 
the construction and installation of plumbing fix- 
tures was inaugurated. 

The "siphon" closet is made in many styles and 
with many different methods of starting the 
siphonic action, but the general principle in all is 
the same, and it is really the only water closer 



107 



The Sanitary Sewerage of Buildings. 

which has been produced which fulfils the require- 
ments before mentioned. Its popularity may be 
seen by an inspection of the stock of any plumbing 
store, or by a glance through the catalogues of the 
makers of water closets or the advertising columns 




Fig. 3S. "Long Hopper" closet. 

of any of the plumbing or engineering journals. 
Man's ingenuity may yet devise a better type of 
closet, but, from present indications, the "siphon" 
closet is destined to have a lengthy stay. Changes 
in the types of flushing apparatus for these closets 



108 



Plumbing Fixtures and Accessories. 

will appear from time to time, and such apparatus 
will occasionally get out of order, notwithstanding 
the most careful usage. 

There are two important points to be observed 
in the setting of a water closet — the floor connec- 
tion and the back venting of the soil pipe beneath 
the fixture. The latter point will be discussed in 
Chapter VII. under the heading "Traps — Back 
Venting." 

In view of the fact that the trap of the modern 
water closet is above the floor, a defective connec- 
tion between the fixture and the soil pipe will 
mean the entrance to the room in which the fixture 
is placed of air from the sewer. Notwithstanding 
that this connection may be made air-tight in the 
beginning, unless the work has been properly done, 
there will be a constant danger from a possible 
break in the joint, due either to the expansion and 
contraction of the soil pipe, or to a movement of 
the fixture. 

To overcome the danger from the movement of 
the soil pipe, a lead bend should always be used to 
connect the fixture with the iron soil pipe; and to 
prevent fracture of the joint by the movement of 
the fixture, the latter should be made as rigid as 
possible, and the gasket between the outlet of the 
fixture and the lead bend should be sufficiently 
elastic to permit of considerable vibration. 



109 



The Sanitary Sewerage of Buildings. 

In the case of fixtures not provided with special 
floor connections, a rubber, asbestos graphite, or 
asbestos string gasket will adapt itself to every 
ordinary movement of the fixture, and preserve the 
joint intact with any reasonable usage of the fix- 
ture. 

To secure an even surface upon which the un- 
derside of the gasket may rest, and to do away 
with the necessity for a thick gasket, a brass flange, 
about three-sixteenths of an inch thick, should be 
soldered to the lead bend and screwed to the floor. 

If the gasket and brass flange are of the proper 
thickness, and the fixture properly set up and firmly 
screwed to the floor, a comparatively firm and, at 
the same time, elastic joint will be the result. 

Where the water closet is to rest upon a cement, 
stone, tile, marble or granite floor, the base of the 
fixture should be fastened to the floor by means of 
bolts set in the floor. Special expansion bolts may 
be obtained for this purpose, and are superior to 
the ordinary lead calked bolts which sometimes 
break the floor and render the making of an air- 
tight joint difficult. 

In making these floor connections, the brass, 
flange and gasket are often dispensed with and 
putty is used in their place. A putty joint may be 
made air-tight for a time, but when the putty has 
hardened, and there is a movement of the lead 



110 



Plumbing Fixtures and Accessories. 

bend or fixture, the putty will be very liable to 
crack, and, for this reason, it should not be used 
for the purpose. 

Figure 39 shows a type of closet provided with 
a threaded floor connection, the threaded thimble 
being soldered to the lead bend and the closet sim- 




Fig. 



ply screwed into the thimble. The usual screws or 
bolts for fastening the closet to the floor are dis- 
pensed with, and the fixture can be removed at any 
time by simply unscrewing it from the thimble. 
Absolute security against leakage of water, or the 
passage into the room of air from the soil pipe, 
through the floor connection, are claimed for this 
attachment. 



Ill 



The Sanitary Sewerage of Buildings. 

Bath tubs — Like the water closet, the bath tub 
has undergone a wonderful change in recent years, 
from the unsightly zinc lined affair, with its wooden 
enclosure, to the sanitary porcelain or porcelain 
enameled fixture of today, with its pleasing interior 
and exterior — a thing of beauty and a joy to the 
lover of cleanliness. 

The modern bath tub is set up with plated fittings 
above the floor, and the connection of the fixture 
with the trap and waste pipe should not be a diffi- 
cult matter, at least in so far as relates to the 
security and permanency of the connection. The 
waste pipe should be not less than one and one-half 
inches in diameter, and should be of lead to a point 
beyond the trap to allow for a possible movement 
of the vertical soil or waste pipe into which it dis- 
charges. It should not be connected with the trap 
of any water closet or slop sink, but should have a 
separate connection with the vertical stack. The 
common method of making this connection is 
through a "Bottle" or "Pot" trap, with a removable 
top, set level with the floor, for the purpose of 
cleansing the trap. 

Of the modern plumbing fixtures, the bath tub is 
the only one which has a concealed trap, and while 
these traps are usually provided with access open- 
ings above the floors, a bath tub with a trap entirely 
above the floor would be a great improvement over 
the present construction. 



112 



Plumbing Fixtures and Accessories. 

Wash basins — Wash basins are usually con- 
structed of porcelain, or porcelain enameled iron, 
in a great variety of styles, and are set up with 
plated fittings all in plain sight. The connection 
with the vertical stacks into which they discharge 
is a very simple process, but the insertion of a piece 
of lead pipe between the fixture and the vertical 
stack, to allow for a possible movement of the lat- 
ter, should not be overlooked. 

The waste pipes of wash basins should not be less 
than one and one-quarter inches in diameter, and 
the connections with the iron pipes, or fittings, 
should be made by means of brass ferrules, calked 
or screwed into the iron pipes, or fittings, and sol- 
dered to the lead pipes by what is commonly known 
as plumber's wiped joints. This method of connect- 
ing iron and lead pipes should be followed through- 
out the entire soil and waste pipe construction. 

An overflow is a necessary part of a wash basin, 
and yet may become a source of offensive odors 
from the accumulation of organic matter upon its 
sides. For this reason, the overflow should not, as 
in many instances, be a part of the basin, but should 
be easily removed for the purpose of cleansing. A 
standing overflow, set in a recess at the rear of the 
basin and properly supported, may be made to serve 
the double purpose of waste plug and overflow, and 
is recommended as a sanitary arrangement of the 
outlet of such a fixture. 



113 



The Sanitary Sewerage of Buildings. 



Slop sinks — Slop sinks are not considered neces- 
sary for ordinary sized dwellings, but they are 
necessary for large buildings, apartment houses, 
hotels, many public buildings, and the dormitories 
of educational institutions, where the slops from 
many rooms, or the dirty water from the washing 

of many floors, will 
have to be taken care 
of by the sewers. 
They should, in every 
case, be of porcelain, 
or of iron with a 
good porcelain en- 
amel, both inside and 
outside. They should 
Fig - 40 - properly be furnished 

with flushing rims and flushing tanks for the pur- 
pose of cleansing the sides after use; and should 
always be furnished with removable strainers, of 
fine mesh, for the purpose of keeping out of the 
sewer matches, hair, broom straws, and other sub- 
stances usually found in slops and in water which 
has been used for the washing of floors. The trap 
should be above the floor, and the connection with 
the soil pipe made in the same manner as for water 
closets. 

Public tolict rooms may be said to include the 
toilet rooms of all buildings to which the general 









^--^ ^2* C-^Ji-J 






AW 


\ a » 




#7 


\?\ 


i^-i&^j^ 


JU 


. ' 



114 



Plumbing Fixtures and Accessories. 

public, or many people not of the same family, have 
access, as hotels ; department stores ; office build- 
ings ; schools ; halls of assembly ; hospitals ; state, 
county and local government buildings; charitable, 
penal and reformatory institutions ; factories ; club 
houses ; railroad stations, etc. 

The plumbing fixtures which will usually be found 
singly or en suite, in the toilet rooms of buildings 
such as I have enumerated are water closets, trough 
closets, latrines, urinals, wash basins, sinks, and 
baths (stationary tub and shower). 

The zvuter closets, zvash basins, sinks, and bath 
tubs of public toilet rooms will not differ materially 
from those designed for use in private toilet rooms, 
to which reference has already been made. In 
some instances, particularly where the fixtures 
would be liable to rough usage, porcelain enameled 
iron may very properly be used in place of all por- 
celain, and the fixtures in such locations may re- 
quire to be made stronger and set more firmly than 
would be required for the toilet rooms of dwellings. 

In the choice of water closets for a public toilet 
room, preference should be given to individual 
closets, of the siphon type, with seat action flush. 
In schools, and in other buildings where very small 
children congregate, closets which depend for their 
flushing upon the depression of the seats for a given 
length of time, have not always given satisfactory 
results, and for such buildings, where water is 



115 



The Sanitary Sewerage of Buildings. 

plentiful, automatic flushing of the closets may be 
resorted to. 




,,i... . . W ■■■ 



■■■:;■ 



'I_u ~"* r *~i~-^ T* lIT T._.l".".'j ' * uwr F •i'i'^~'- t ~T' 



_. __, — _ — . . — . y 



X 



Fig. 41. 

Trough closets — so named by reason of their 
shape — are often made use of in public buildings, 
particularly in school houses, and are made in vari- 
ous styles, one form of which is shown in Figure 40 
and a cross section of the same in Figure 41. 




116 



Plumbing Fixtures and -Accessories. 

The trough is usually made of cast iron, and 
sometimes of glazed stoneware, is trapped at the 
outlet, and has an automatic flush. 

In comparison with a range of substantial siphon 
closets, with seat action flush, as a rule, the trough 
closet is considered inferior, and for the following 
reasons : 

i. A considerable quantity of excreta may accu- 
mulate in the trough, and give rise to offensive 
odors, between the times of flushing, and at such 
times as the flushing apparatus may be out of order. 

2. The sides of the trough may become fouled 
above the water standing in the trough, and the 
fouling may be too high or too dry to be reached 
or removed by subsequent flushings. 

3. Notwithstanding the usual attention given to 
these closets, the inside of the trough will become 
discolored, and finally rough, and a permanent coat- 
ing of foul smelling filth is the result. This is true 
particularly of closets in which the troughs are 
made of iron with inferior coatings of enamel. 

In addition to the foregoing objections, the un- 
necessary waste of water, and the time and labor 
for supervision and cleansing, which such fixtures 
entail, may be considered valid objections to their 
general use. 

Perforated pipes, for maintaining a clean condi- 
tion of the sides of the trough, are provided in some 
makes of this type of closet, but the extent of the 



117 



The Sanitary Sewerage of Buildings. 

surface to be flushed is very great and necessitates 
a considerable increase in the already large amount 
of water required for the periodical flushing of the 
trough. Further, unless the flushing is continuous, 
or nearly so, and the sides of the trough should be- 
come fouled between the times of flushing, it is 
doubtful if the auxiliary flushing would be suf- 
ficient to detach the dry, or partly dry, excreta from 
the sides of the trough. 

Where the amount of water used would not be a 
consideration, and providing the most careful and 
constant attention could be given to them, trough 
closets, of the best types, well ventilated, and fre- 
quently flushed, might be considered permissible for 
some buildings where water closets would be sub- 
ject to rough usage. 

The ventilation of trough closets will be referred 
to in a subsequent part of this chapter, under the 
heading of "Local Vents." 

Latrines. — Properly speaking, the term latrine 
may be applied to almost any privy or water closet, 
but more particularly to the privies or water closets 
usually found in camps and in some hospitals. For 
our purpose, it will be taken to mean the type of 
fixtures represented by Figure 42, designed for use 
in the toilet rooms of buildings of a public or quasi 
public character. 

Like the trough closet, the latrine has been sub- 
jected to much criticism in recent years, and the 



118 



PlUxVibing Fixtures and Accessories. 

makers of latrines have endeavored to keep pace 
with the criticisms, by changes and improvements 
in their wares, until now there are in the market 
latrines which, when set up, in general appearance 




Fig. 42.* 

and in some important features, do not differ mate- 
rially from ranges of individual closets. 

In some makes of latrines we have an all porce- 
lain bowl, and in some of these the top is molded to 
form a seat and thus dispense with the usual wooden 



Copyrighted by the J. L. Mott Iron Works. 



119 



The Sanitary Sewerage of Buildings. 

seat. From a sanitary standpoint, this may be con- 
sidered commendable, but as a latrine may often be 
used as a urinal, the porcelain seat may become 
fouled and rendered unfit for the purpose for which 
it was designed. Wooden seats are liable to be 
fouled in the same manner, but the people, espe- 
cially the traveling public, have received consider- 
able training as to the proper methods of using 
water closets, and it is believed the wooden seats 
would be less likely to be put out of commission, in 
the manner indicated, than would the porcelain 
seats. Another objection which may properly be 
made to the porcelain seat is that in cold weather, 
particularly where the room in which the latrine 
might be located was not very warm, the seat would 
be a source of discomfort to those using the fixture. 

There is another type of latrine in which the 
whole of the water for flushing is made to pass 
through the bowls, in much the same manner as in 
ordinary water closets, and thus secure a more effi- 
cient flushing and cleansing of the bowls than could 
be obtained by the usual under flush, or by a divi- 
sion of the flush, partly beneath and partly through 
the bowls, as in some makes. 

There is still another type of latrine in which the 
base of the fixture is concealed by a raised wooden 
floor, upon which the bowls are set, giving the ap- 
pearance of a range of individual water closets. 



120 



Plumbing Fixtures and Accessories. 

In the endeavor to meet the objection relative to 
foul odors which may arise from the retention of 
excreta in the bowls between the times of flushing, 
many latrines are provided with local vents, and the 
methods of terminating these vents are many and 
are very varied. This phase of the subject will be 
referred to in a subsequent part of this chapter, un- 
der the heading, "Local Vents." 

Placed in comparison with a range of substantial 
water closets, with seat action flush, the latrine does 
not possess any advantage over the former, and is 
open to the following objections : 

i. The base of the fixture is unsightly, a dirt 
collector, and renders cleansing of the floor beneath 
the fixture difficult. As previously stated, in at least 
one make of latrine, this objection has been met 
by the concealing of the base of the fixture under a 
raised wooden floor, but this method is open to the 
more serious objection of providing a space for the 
collection of water and filth and which cannot be 
cleansed without removing the fixture. 

2. In the absence of thorough ventilation of the 
bowls, the retention of filth in the bowls between the 
times of flushing will give rise to foul odors in the 
toilet room ; and even where the bowls are well ven- 
tilated, the presence of filth in the bowls for any 
length of time would be disgusting to persons using 
the fixture. 



121 



The Sanitary Sewerage of Buildings. 

3. To overcome the objection relative to the re- 
tention of filth in the bowls, nearly constant flushing 
of the fixture would be necessary, and this would 
entail a considerable waste of water, which, in many 
instances, would be a serious objection. 

4. In latrines where the bowls are provided with 
flushing rims, the sudden and unlooked for dis- 
charge of a considerable quantity of water into 
bowls which might be in use at the time would, for 
obvious reasons, be considered an objection. 

Like the trough closet, the latrine was at one time 
considered a very suitable fixture for the toilet 
room of a public building, but the advent of a really 
sanitary water closet, which will stand considerable 
rough usage, which is as nearly self-cleansing as 
can be expected, and which does not consume a 
large amount of water, has placed the two fixtures 
in question at a disadvantage. 

Where a latrine might be considered a necessity, it 
would be well to choose a fixture in which the water 
for flushing is made to pass through the bowls, and 
to place the base of the fixture beneath an imper- 
vious floor, so that there would be no interference 
with the cleansing of the floor beneath the fixture. 
Urinals. — Of the foul odors commonly found in 
the toilet rooms of public buildings, by far the 
greater portion may be charged up to the urinals ; 
and the evolution of odors from a urinal is usually 
continuous and very difficult to prevent. For these 



122 



Plumbing Fixtures and Accessories. 

reasons, much care should be exercised in the choice 
of such fixtures and in the care of the same when 
set up. 

Urinals are usually constructed of porcelain, en- 
ameled iron, soapstone, slate, stone, and cement. 
Except in schools, and in other buildings where they 
would be subject to rough usage, preference should 
always be given to the porcelain fixture. Where 
iron is used, it should have a substantial porcelain 
enamel. For stall urinals, and for the backs and 
partitions of urinals set in a range, the best grades 
of soapstone may be considered permissible. It is 
scarcely necessary to state that materials having a 
rough surface, or which are porous in character, as 
stone and cement, are entirely unsuited for the con- 
struction of urinals, and could not be kept free from 
odors. 

The three principal types of urinals are repre- 
sented by Figures 43, 44 and 45, that shown in 
Figure 43 being suitable for almost every location 
and easily kept clean. There are many different 
methods of trapping urinals of this type, some hav- 
ing a metal trap, in plain sight, others a concealed 
trap behind or within the fixture, and other a trap 
beneath the floor. In the latter case, the one trap is 
usually made to serve the double purpose of trap- 
ping the urinal and floor drain. As in the case of 
other modern plumbing fixtures, the trap of this 
or any other type of urinal should be in plain sight, 



123 



The Sanitary Sewerage of Buildings. 



and provided with means for cleansing the same. 
Urinals of this type should be provided with auto- 




Fig. 43.* 
matic flushing tanks, of small capacity, and the 



"Copyrighted by the J. L. Mott Iron Works. 

124 



Plumbing Fixtures and Accessories. 

flushing should be frequent, or otherwise, according 
to the number of times the fixtures are likely to be 
used. 

The urinal shown in Figure 44 is often preferred 
for the toilet rooms of railroad stations, public parks 




Fig. 44. 

and places of a similar character, and many public 
buildings. They are usually made of slate, and 
sometimes of soapstone or imperial porcelain. Of 
the three materials, by reason of its smooth, white 
glaze, porcelain is by far the most suitable in the 
points of cleanliness and durability. The best grades 
of soapstone are considered superior to slate for this 
purpose, are much less expensive than porcelain, 



125 



The Sanitary Sewerage of Buildings. 

and with proper care may be maintained in a sani- 
tary condition. Urinals of this type should be con- 
stantly flushed by means of a perforated pipe, or by 
a "Spreader" in each stall. 




Fig. 45. 

The type of urinal shown in Figure 45 is best 
suited for the toilet rooms of school buildings, or of 
any building where it would be subject to rough 
usage. For schools frequented by young boys, the 
trough should not be more than sixteen inches 
aboye the floor, and flushing should be frequent, 
particularly during recess. 



126 



Plumbing Fixtures and Accessories. 

The ventilation of urinals will be considered in a 
subsequent part of this chapter, under the heading, 
"Local Vents." 

Shower baths. — Shower baths, or as they are 
sometimes termed "rain baths," are usually found 
in connection with the toilet rooms of gymnasiums, 
hospitals, penal institutions, public bath houses, and 
in some factories and schoolhouses. 

Placed in comparison with the common bath tub, 
the shower bath possesses several advantages over 
the former, chief among which may be mentioned 
its tonic effect upon the human system, economy in 
the amount of water consumed, and thorough 
cleansing of the body. 

It is scarcely necessary to state that every portion 
of the walls, partitions and floors in the immediate 
vicinity of the shower should be constructed of 
smooth and impervious materials, and the drainage 
from the shower arranged in a sanitary manner. 

Where a number of showers are in a row, or ad- 
jacent to each other, and the appearance of flow 
gutters would not be an objection, the entire floor 
of the toilet room could be drained by flow gutters, 
all converging to one common trap, in which case 
the floor drain shown in Figure 20, Chapter III., or 
other equally good trap, should be used. Bell traps 
are frequently used for this purpose but, for rea- 
sons given in Chapter III., are not considered suit- 
able or safe. 



127 



The Sanitary Sewerage of Buildings. 

Local vents. — Local vents are intended for the 
removal of foul odors from water closets, trough 
closets, latrines, urinals and slop sinks, and should 
not be confounded with the vents provided for pre- 
venting the siphonage of the traps of fixtures. 

Where local venting is to be carried out, the fix- 
tures are usually provided with special openings 
for the purpose. In water closets, and in fixtures 
having bowls of corresponding shape, the vent 
openings are usually made at the rear of and near 
to the tops of the bowls ; in trough closets, at some 
point near to the tops of the troughs ; and in uri- 
nals, they are usually at or near to the outlets of the 
fixtures. To be of service, the vent pipes leading 
from the fixtures should be devoid of sharp turns, 
and should be connected with heated flues, con- 
structed or suitable for that purpose and extended 
above the roofs. They should never be connected 
with the smoke flue of any-stove, fireplace or fur- 
nace, nor with the ventilating flue of any inhabited 
room. 

Local vents are not considered necessary for the 
water closets, or other fixtures, in well ventilated 
toilet rooms of dwellings, and no water closet, or 
other fixture, should be placed in any part of a 
dwelling which cannot be properly ventilated with- 
out the aid of local vents. In toilet rooms fre- 
quented by many people, particularly where such 
rooms are located in the basements of buildings, the 



128 



Plumbing Fixtures and Accessories. 

local venting of water closets, and the slop sinks, if 
any, may be considered an advantage. Trough 
closets, latrines and stall urinals should always be 
provided with local vents, of ample size, and having 
an upward inclination from the points where they 
join the fixtures. 

In one type of latrine, provision is made for car- 
rying the local vents downward to the floor before 
they are connected with the vertical flues, and one 
reason given for so doing is that "foul odors are 
heavier than air and naturally go down." The dif- 
ference in the weights of a very short column of 
ordinary air and a corresponding column of air such 
as would be found in the bowl of a latrine, during or 
immediately after use, would be extremely small, 
and could not be considered as an auxiliary to the 
draft in the vertical flue. Further, in carrying the 
vent pipe downward, the air would have to make at 
least one unnecessary square turn in its passage to 
the vertical flue, and each square turn means a loss 
of about fifty per cent in the draft. 

Where steam heat is available, a coil of steam 
pipe in each vertical flue to which the local vents 
are connected would ensure a good draft. In warm 
weather and at such times as steam heat might not 
be available, the vertical flues should be heated by 
a stove or gas jet. In the absence of either steam 
or gas, or where a stove might be considered too ex- 



129 



The Sanitary Sewerage of Buildings. 

pensive for the purpose, a small exhaust fan might 
be made to serve the purpose of securing a positive 
draft. 

Where the local vent of a stall urinal is made suf- 
ficiently large, and begins at the floor level, the 
usual vent register for the ventilation of the toilet 
room may be dispensed with. 

Arrangement, lighting and ventilation of toilet 
rooms. — The arrangement of the fixtures in a toilet 
room will not materially affect its sanitary condition, 
but there is one point which is often overlooked and 
which may incommode the occupants of a dwelling, 
particularly where a number of people may be likely 
to use the toilet room, viz., the location of the bath 
tub and water closet. Wherever possible, these fix- 
tures should be located in separate rooms, or 
screened off in such a manner that the fixtures may 
each be used at the same time, if necessary. 

That a toilet room should be well lighted and 
ventilated goes without saying, and yet there are 
very many such rooms in which both light and the 
necessary changes of air are woefully lacking. 
Whenever possible, these rooms should have at least 
one outside wall so that light and summer ventila- 
tion can be obtained by means of windows. Where 
this is not possible, and the toilet room is on the top 
floor of a building, such lighting and ventilation 
may be secured by means of a skylight, or, better 
still, where the roof is flat, by means of a lantern 



130 



Plumbing Fixtures and Accessories. 

light. Where the toilet room is not located on the 
top floor of a building, a special light and vent shaft, 
terminating in a lantern light, is deemed necessary. 
For the proper ventilation of a toilet room in 
winter, and at such times as the windows could not 
be open, a special vent flue, of ample dimensions, 
and extended above the roof, should be provided. 
Where steam heat is available, a few feet of steam 
pipe placed at the base of such a flue would ensure a 
positive draft. As previously stated, where a stall 
urinal is used, the ventilation of the toilet room in 
which it is located may be accomplished by means 
of the local vent, provided the same is made large 
enough for this purpose. 



131 



CHAPTER VII. 

Traps. 

TNa general sense, the word "trap" is intended to 
mean a snare, an ambush, a strategem, or any 
device by which animals, birds or human be- 
ings may be caught unawares. Used in connec- 
tion with the well-known and useful appendage to 
plumbing fixtures of all kinds, the word "trap" is a 
misnomer, and should be abandoned in favor of a 
better name, as interceptor, barrier, or water seal. 
Either of these would correctly describe the func- 
tions of a trap, viz., the prevention of the passage 
of air from a sewer through the outlets of plumbing 
fixtures or other openings in the sewer, without ma- 
terially affecting the flow of sewage into or in the 
sewer. One of the principal requirements of a trap 
is that it shall be self-cleansing, and hence it is not 
intended for the purpose of "catching unawares" any 
part of the sewage which may pass through it; 
neither is there anything in the air of a sewer which 
could or should be "caught" by a trap in the manner 
indicated. Long usage of the word "trap" will 
probably act as a deterrent to any such change as 
suggested, nevertheless the suggestion is worthy of 
consideration, and might at some time accomplish 
the end for which it is made. 



132 



Traps. 

Traps are, to a considerable extent, unnecessary 
evils, but there has not been discovered any device 
which can take their place. The necessity for a trap 
in connection with each plumbing fixture has never 
been questioned ; the necessity for or the wisdom of 
the placing of a main trap in a house sewer has been 
the subject of much controversy, to which reference 
was made in Chapter II ; but the use of a trap at 
the foot of a soil pipe, a vertical waste pipe stack, 
or at any point in a sewer between the main trap 




Pig. 46. 

and the traps of plumbing fixtures, has long since 
and almost universally been condemned, for the rea- 
son that it is entirely unnecessary, a serious hin- 
drance to the flow of sewage, and an obstacle to the 
proper ventilation of the sewer. 

Forms of Traps. — Traps may be divided into three 
principal classes : Main traps, fixture traps, and 
floor traps, the various forms of which are based 
upon the principle of a sag in a pipe, as illustrated 
by Figure 46. 

Main traps have already been considered in 
Chapter II, and floor traps in Chapter III, there- 



133 



The Sanitary Sewerage of Buildings. 

fore the following remarks on traps will have spe- 
cial reference to the traps of fixtures. 

The number of traps, of different types, which 
have been and are at the present time upon the mar- 
ket is legion. There are, however, but few traps 
which can lay claim to the term sanitary, and these 




Pig. 47. 

are limited almost entirely to those traps which 
have a uniform circular cross sectional area 
throughout, five forms of which are shown in 
Figure 47. 

Without adequate protection, however, the water 
seals of this class of traps are easily destroyed, and 
it was for this reason, principally, that so many dif- 



134 



Traps. 

ferent types of traps have been introduced. In 
almost every instance, however, the attempt to over- 
come this defect in the round pipe traps, so-called, 
has resulted in the production of a trap which was 
defective in some other particular, notably in re- 
spect to its self-cleansing quality, examples of which 




Fig. 48. 

are shown in Figure 48. Many traps designed to 
overcome the defect in the round pipe traps before 
mentioned are prohibited in the most recent plumb- 
ing codes, of which the following extract from the 
Cleveland code is a sample : 

"Every trap on a drainage or plumbing system 
shall be self-cleaning. No bell, bottle, or D trap 
shall be used. No form of trap which depends 



135 



The Sanitary Sewerage of Buildings. 

upon the action of movable parts for its seal shall 
be used. No trap which depends upon concealed 
interior partitions or deflectors for its seal or re-seal, 
or which has an interior partition that, in case of 
defect, would allow the passage of sewer air, shall 
be used, except for earthenware fixtures where the 
seal of the trap is plainly visible." 

In this code, however, in addition to the class of 
traps shown in Figure 47, certain resealing traps — 
modifications and combinations of plain and drum 
traps — together with anti-siphon traps are per- 
mitted, provided they will stand the tests provided 
in the code. These tests relate, principally, to the 
ability of traps to resist siphonic action such as they 
would be subject to in actual practice. 

For the purpose of securing the greatest possible 
cleanliness in every portion of the sewerage sys- 
tem of building, in the selection of traps prefer- 
ence should usually be given to the class of traps 
shown in Figure 47, and precautions taken to pre- 
vent the reduction or destruction of their water seals 
by siphonic action, etc., as described in a subsequent 
part of this chapter. 

Notwithstanding that a trap may be considered 
self-cleansing, it will sooner or later become a re- 
ceptacle for accumulations of grease and other 
solids which may give rise to foul odors or form the 
nucleus of a stoppage, and, for this reason, every 
such trap should be provided with a clean-out, but 



136 



Traps. 

the latter should always be placed below the water 
line of the seal so that a leak will be detected. 

Loss of Seal in Traps. — The reduction or de- 
struction of the water seal in a trap may be due to 
one of four principal causes : siphonage, back pres- 
sure, evaporation, or capillary attraction. It is 
sometimes due to the momentum of the water pass- 
ing through a trap. The most common cause, and 
that to which special attention is directed, is that of 
siphonage, or the suction produced by the flow of 
sewage in a pipe in quantity sufficient to fill the pipe 
at some point in the form of a piston or plug. The 
mass of water drives before it the air contained in 
the pipes and leaves behind it a partial vacuum, 
greater or less according to the rapidity with which 
air may enter the pipe to restore the normal pres- 
sure. If such a pipe was of uniform size through- 
out, and open at both ends — as in the case of a 
well ventilated soil pipe of moderate height — the 
normal pressure of air in the pipe would be restored 
without undue influence upon the water seals of any 
traps which might be connected with it; but if the 
pipe was closed or reduced in size at its upper end, 
or of such a height that air could not pass down it 
with sufficient rapidity, the greater pressure of air 
on the house side of the water seals of the traps 
would force air through the traps and with it some 
of the water, and thus weaken or destroy the seals. 



137 



The Sakitary Sewerage of Buildings. 

Many experiments have been made to determine 
the conditions under which the siphonage of traps 
is possible, and vice versa, and it has been found 
that very much depends upon the depth of the water 
seals of the traps ; the relative sizes of the traps and 
the vertical stacks with which they are connected; 
the horizontal distance between the traps and the 
vertical stacks; and the sizes of extensions of the 
vertical stacks above the roofs. 

Among the earliest recorded experiments in rela- 
tion to trap siphonage are those made by S. Stevens 
Hellyer, of London,** by which he demonstrated 
that round pipe traps, properly constructed and 
ventilated, are free from injurious effects from 
siphonage, for if they could not be unsealed when 
connected to pipes of the same diameter as them- 
selves, nor of smaller diameter, they are more cer- 
tain to hold their seals when connected to pipes of 
larger diameter, where the friction, and therefore 
the suction power of a corresponding discharge of 
water, would be much less. 

From experiments conducted for the Boston City 
Board of Health, by J. Pickering Putnam and L. 
Frederick Rice, and recorded in "The American 
Architect and Building News," June 7, 1884, it was 
learned : 

1. * * * * "that the siphonic action which 
may be produced by a trapped plunger water closet 

**"The Science and Art of Sanitary Plumbing," by S. S. 
Hellyer, 1882. 

138 



Traps. 

under certain simple conditions which are likely to 
be encountered in plumbing, is sufficient to unseal 
small S traps, such as are ordinarily used for lava- 
tories, though they be ventilated either at or below 
the crown in the manner prescribed by the plumb- 
ing regulations with vent pipes of the full size of the 
trap, and that it makes no material difference as to 
siphonage whether the vent pipe be applied at the 
crown or at a considerable distance below it. This 
action takes place even when the pipes are clean 
and new. When partially closed or clogged with 
sediment the results would be even more serious. 

2. * * * * - "that the power of resistance 
of 'pot-traps' depends upon their size and more par- 
ticularly upon the diameter of the body. 

3. That "* * * * the resisting power of 
pot-traps of equal depth of seal is in direct propor- 
tion to the diameter of the body. 

4. That "no pot-trap whose body does not ex- 
ceed in sectional area fifteen times that of each of 
its arms or connecting pipes can be accepted as 
anti-siphonic under all conditions likely to be en- 
countered in plumbing. 

5. That "pot-traps having bodies 6" in diameter 
and having iy 2 " or 1%" connections may, however, 
be considered safe when they are not exposed to 
the repeated action of plunger zmter-closets of the 
largest zvater capacity. 

139 



The Sanitary Sewerage of Buildings. 

By reason of a conflict of opinions and deduc- 
tions of authorities who had, up to the year 1885, 
made experiments in relation to trap siphonage, it 
was impossible to form a definite conclusion upon 
the subject, and this led to a series of experiments, 
in that year, at the Museum of Hygiene, United 
States Navy Department, Washington, D. C, by 
Glenn Brown, an architect of that city. These, ex- 
periments were said to have been "conducted to 
get at the real facts," the apparatus at the Museum 
being arranged "more nearly in accordance with 
the methods in ordinary use, than has been the case 
in other experimental plants." The principal deduc- 
tions from these experiments were : 

1. That the seals of ventilated traps are safe 
against siphonage. 

2. That, as a rule, the seals of unventilated 
traps are never safe from siphon action. 

3. That traps connected on a horizontal pipe 
and fixtures discharging on the same level into 
horizontal pipe apparently have no effect on un- 
ventilated traps. 

These experiments led to a wordy and public 
discussion between Mr. Brown and Mr. J. P. Put- 
nam, in which Mr. Brown seems to have had the 
last word. 

More recently a series of experiments on this 
subject was made under the auspices of the Munici- 

140 



Traps. 

pal Building Department by Herr Unna, a sanitary 
engineer, of Cologne, Germany, for the translation 
of the record of which we are indebted to W. P. 
Gerhard, C. E., of New York. So far as can be 
learned these experiments were confined to the 
common round pipe type of traps. From a sum- 
mary of the experiments it is learned : 

i. That the greatest depth of water seal at which 
traps of from ify" to 2^2" diameter will be self- 
cleansing is four inches, and that, other things 
being equal, this depth is necessary to render traps 
of the sizes given safe against loss of seal by 
siphonage. For the traps of water closets a depth 
of seal of at least two inches was found to be 
necessary to prevent siphonage. 

2. That siphonage does not readily take place 
where the cross sectional area of a soil or waste 
pipe is one size larger than that of a trap discharg- 
ing into it, as, for instance, a 2" waste pipe for a 
V/2" trap, a 2y 2 " pipe for a 2" trap, and so on. 

3. That where a trap is not more than 3.3 feet 
distant from the vertical soil or waste pipe, siphon- 
age does not readily take place. 

4. That in order to prevent the siphonage of 
traps which may be connected with them the verti- 
cal soil or waste pipes should be continued in full 
size, and with as few offsets as possible, to a point 
above the roof, and that it woidd be still better to 



141 



The Sanitary Sewerage of Buildings. 

enlarge the upper ends of such pipes two inches 
from a point twenty inches below the roof. 

With respect to the requirement in the preced- 
ing paragraph, it should be stated that in the vari- 
ous plumbing codes in the United States it is gen- 
erally specified that the vertical soil pipes shall be 
continued their full calibre above the roof, and 
the vertical waste and vent pipes enlarged to at 
least four inches in diameter before they pass 
through the roof. To prevent a serious reduction, 
by frost, in the bore of such extensions, in the most 
recent codes provision is made for the enlargement 
of all soil, waste and vent pipes before they pass 
through the roof, with a minimum size of four 
inches for the waste and vent pipes. 

In 1889-90 extensive experiments in trap siphon- 
age were made at the Stevens Institute of Tech- 
nology, Hoboken, N. J., by James E. Denton, M. E., 
having for their special object the determination 
of the ability of a certain patented Anti-Siphon 
Trap Vent "to protect simple S traps against the dis- 
turbing influences due to the downward flow of 
water in waste pipes, such as are common to 
plumbing construction." The results of these ex- 
periments were published in Vol. XVI of the Trans- 
actions of the American Public Health Association 
and contribute some new data upon the subject, 
chief among which may be mentioned the follow- 
ing: 



142 



Traps. 

i. That, contrary to the general impression, the 
greatest vacuum or suction is not produced when 
a waste pipe is supplied with a jet of water of the 
same diameter as the pipe. Thus, when a 2" waste 
pipe received the flow of water from a tank through 
a 1^2" opening a mercury pressure gauge attached 
to the pipe at a certain point showed 24" of vacuum ; 
but when a 2" orifice supplied the 2" waste pipe 
only 18%" of vacuum was recorded. The cause of 
the superior vacuum with the smaller stream was 
attributed to "the greater friction of the larger 
stream, resulting in a less velocity of flow, and 
hence a less intensity of vacuum," and to the fact 
that "the smaller stream causes an induced current 
of air to accompany it, which increases the volume 
of displacement, and may have considerable effect 
in rarefying the air in the branches of the waste 
pipe leading to the mercury column." It was also 
learned "that either a \y 2 or 2-inch stream deliv- 
ered into a 4-inch waste pipe will produce greater 
siphonage effect than the same stream in a 2-inch 
waste pipe, and yet the vacuum registered by a 
gauge will not exceed three-eighth inches of mer- 
cury." It was further learned that "a 2-inch stream 
in a 4-inch pipe does not * * * * produce as 
great a siphonage influence as the same quantity of 
water discharged through a 4-inch opening into a 
4-inch pipe." 



143 



The Sanitary Sewerage of Buildings. 

2. That, contrary to the frequent assumption* 
the greatest vacuum with a given stream of water 
does not occur at the lowest fixture on a line of 
waste pipe, but decreases as the mercury gauge is 
applied nearer to the bottom of the waste pipe. 
This was said to be "directly traceable to the 
dynamic principle controlling the pressure of a 
column of descending water," i. e., "that pressure 
of such a column shall vary at different levels, by 
amounts representing the weight of the column above 
the point of observation, just as though the water 
was at rest, or the pipe plugged at the bottom. 
Hence, the nearer to the bottom a fixture is attached 
the greater the pressure from the superincumbent 
column above, and hence the less the vacuum." 

3. That a iy 2 " wrought iron vent pipe, not more 
than 13^2 feet long, and having not more than two 
elbozvs, will safely protect the seal of a simple S 
trap, having only iy 2 " depth of seal, against the 
greatest suction siphonage influence which can be 
produced by any How of water into a 2." waste pipe 
of any height. 



*The popular idea relative to the action of a falling body of 
water in a long vertical line of soil or waste pipe is substan- 
tially as stated in the following extract from "Hygiene and 
Public Health," by Louis Parkes, M.D., 1889 : 

"Where one soil pipe receives the discharges of several water 
closets on different floors the passage of the contents of one of 
the upper closets down the soil pipe may cause the water in the 
trap of one of the lower closets to be drawn off, owing to the 
suctional force of the downward current of air caused by the 
descent of the liquid in the soil pipe." [The italics are mine. T. 
S. A.] 

144 



Traps. 

In a well designed house 
sewer the danger from the 
loss of seal in the traps of 
fixtures by back pressure 
should not be great. Under 
certain conditions, however, 
it may become a source of 
considerable danger, as 
may be seen by reference to 
Figure 49, in which the 
column of air in the lower 
part of the soil pipe C is 
retarded in its descent, 
causing a compression of 
the air and a rise of water 
on the house side of the 
trap B. Air will be forced 
through the trap, as shown 
by the arrows, and, if the 
falling body of water from 
the trap A is considerable, 
the water in the trap B 
may be forced completely out of the trap. After the 
pressure of air on the water in the trap B is re- 
lieved the water in the trap will fall and, in regain- 
ing its normal level, some of the water will escape 
from the outlet of the trap, thus reducing the seal. 
In a shallow trap this would mean a' considerable 
weakening of the seal. The circumstances under 




Fig. 49. 



145 



The Sanitary Sewerage of Buildings. 

which such a condition as that just described may 
occur may be found in many buildings in which the 
sewerage is believed to be danger proof. A sudden 
bend at the foot of a soil or waste pipe ; a long line 
of horizontal sewer, of small dimensions, between 
the foot of a soil or waste pipe and the fresh air 
opening; or the clogging, or partial clogging, of 
the fresh air opening or of the vent pipe of a fix- 
ture trap, may, singly or together, cause a serious 
retardation of the air moving before a descending 
column of water in the soil or waste pipe, and a 
serious disturbance of the water in the traps of fix- 
tures on the lower floors. 

In the experiments on trap siphonage, previously 
referred to, many interesting points and diverse 
opinions were brought out relative to the influence 
of back pressure on traps, the most important of 
which are as follows: 

[From the report of Glenn Brown.] 

"Back pressure seems, from the experiments, to 
be a more important feature in plumbing than is 
generally supposed. Although the fresh air inlet 
was open the air confined in the pipes almost in- 
variably found egress more easily through traps on 
second and first floors than through the opening near 
the foot of the soil pipe. No trap withstood back 
pressure better than the others." 



146 



Traps. 

[From the reply of J. Pickering Putnam to the re- 
port of Glenn Brown.] 

"Back pressure may be easily guarded against by 
simpler methods than by trap-venting, one of 
which methods is to connect the waste pipe of 
the trap with the soil pipe at a point beyond 
the bend which causes the back pressure. This 
can always be very easily done in practice. 
Another method is to set the trap far enough 
below the fixture to permit of the formation in the 
waste pipe, above the trap, of a column of water 
long enough and heavy enough to resist the great- 
est pressure of air likely ever to be encountered in 
good plumbing. The trap must then be constructed 
with sufficient water capacity to fill such a pipe. In 
the experiments for the Boston Board of Health 
the length of pipe required in the worst cases which 
could be encountered in good plumbing was found 
to be from fourteen to eighteen inches. This method 
could always be easily applied in practice in places 
where back pressure was expected and the other 
method was not convenient." 

[From the reply of Glenn Brown to J. Pickering 
Putnam.] 

"I have found that sewer air is driven into the 
house by back pressure from friction in the pipes, 
and that no special bend can be located at the point 
of such friction. The sides of a straight pipe seem 



147 



The Sanitary Sewerage of Buildings. 

to cause all the friction that is required for such 
back pressure. If the assumed objectionable bend 
could be located and the waste pipe attached below 
the bend, in some cases if not in most cases, the waste 
pipe would approximate the length of the soil pipe. 
For instance, wash basin in third story, assumed 
frictional bend near the fresh air inlet outside the 
house, the waste pipe would necessarily run through 
three stories and cellar. Back pressure of this char- 
acter does not force the water up as a mass into the 
pipe between the fixture and trap, but the sewer air 
is forced through the seal in the form of bubbles, as 
I have stated in my experiments. No matter how 
far below the fixture a trap was placed the sewer 
air would be forced through the trap." 

[From the report of James E. Denton.] 

"The general conclusion is therefore warranted 
that with a waste system constructed in accordance 
with the accepted rules of good plumbing practice 
the amount of back pressure liable to be developed 
at the foot of vertical lines, while small, may ab- 
stract water from a three-quarter S trap by the up- 
ward current of gas, clue to back pressure, so as to 
destroy a ijA -inch seal if protected by a vent pipe." 

Under ordinary conditions, the reduction of the 
water seal of a trap by evaporation need not, usu- 
ally, be taken into consideration. 

148 



Traps. 

Where plumbing fixtures are not often used, the 
vvater seals of the traps may become considerably 
weakened by evaporation, and, for this reason, the 
depth of seal of fixture traps should be as great as 
would be consistent with the rule that every such 
trap should be self-cleansing. This rule may be ig- 
nored, however, in the case of the traps of floor 
drains, which, as shown in Chapter III, should be 
constructed with large and deep water seals, with 
the view of retaining the solid matters which may 
gain access to them and of preventing a serious loss 
of seal, by evaporation, during the time they are 
not in use. 

The rapidity with which evaporation of water 
from a trap will take place will depend largely upon 
the presence, or otherwise, of a constant current 
of air in the vicinity of the outlet of the trap, such 
as would be produced by a trap vent ; and, in a 
lesser degree, upon the humidity of the air in the 
room in which the trap may be placed or in the 
soil or waste pipe with which it may be connected. 

From a report of experiments made by J. P. Put- 
nam and L. Frederick Rice,* relative to the evap- 
oration of the water seals of traps, it is learned : 

* * * "(i) that a rapid evaporation of the 
water-seal of traps takes place when they are ven- 
tilated at or near the crown, and that evaporation 
goes on both in winter and in summer, and in ordi- 



*"American Architect and Building News," June 7, 1884. 

149 



The Sanitary Sewerage of Buildings. 

nary unheated flues, as well as in flues artificially 
heated. The evaporation is most rapid in winter 
or with flues artificially heated, and slowest in sum- 
mer, especially in damp weather. * * * 

"(2) That in winter the evaporation produced 
by ventilation is so rapid as to destroy the seal of 
an ordinary 1^/2" machine made S-trap in from 
four to eleven days, according to the nature of the 
current. 

"(3) That without ventilation, or with the ven- 
tilating-flue taken from a considerable distance be- 
low the crown, the evaporation of the water-seals 
of traps is exceedingly slow, and that unventilated 
traps having a considerable water capacity may be 
considered perfectly secure against this danger un- 
less they are left unused for years at a time." (The 
italics are mine. — T. S. A.) 

According to the report in question, under the 
ordinary conditions met with in a dwelling, and with 
the usual trap ventilation, on an average, the seal 
of an unused iy 2 " S trap may be expected to lose 
about one-eighth of an inch in depth per diem, the 
daily loss beginning with about one-fourth of an 
inch on the first day and decreasing as the depth 
of water in the trap decreases. In the absence of 
trap ventilation, however, the rate of decrease may 
not average more than one-thirty-second to one- 
sixteenth of an inch in ten days. 



150 



Traps. 

The loss of depth of water seal in a trap by cap- 
illary attraction will depend, largely, upon the shape 
of the trap and upon the accidental, careless or wil- 
ful discharge into the trap of a foreign porous sub- 
stance, as hair, lint, jute, sponge, rag or twine. In 
a self-cleansing and frequently flushed trap, the 
danger from this source will be very small, because 
the shape of the trap will not permit of the reten- 
tion within it, for any length of time, of any sub- 
stance capable of producing capillarity. In a trap 
having an interior partition around which the 
sewage must pass in its passage to the outlet, the 
probability of the lodgment of foreign substances 
in the trap will be considerable. But the lodgment 
in the trap of any of the substances mentioned will 
not, necessarily, produce capillarity of any conse- 
quence. The capillaries must be in quantity and of 
sufficient length to dip into the water at one end 
and extend over the outlet of the trap at the other 
end. Even then, so we are informed by J. Picker- 
ing Putnam, who made experiments along these 
lines, capillarity will not take place if the outlet of 
the trap is more than 3^ inches above the level of 
the water when at rest in the trap. 

Of the several means described, whereby the 
water seals of traps may become weakened or de- 
stroyed, siphonage and back pressure are paramount 
in importance and demand the most careful consid- 



151 



The Sanitary Sewerage of Buildings. 

eration by those entrusted with the design and in- 
stallation of the sewerage of buildings. , 

As a rule, the usual meth- 
ods for the prevention of si- 
phonage may also be relied 
upon for the prevention of 
serious back pressure, and 
vice versa, therefore a sepa- 
rate consideration of these 
questions will not be neces- 
sary. 

There are two principal 
methods by which the water 
seal of a trap may be protect- 
ed against siphonage, viz., 
back venting of the trap, or 
the attachment to the trap, or 
( f (J to the waste pipe near to the 

trap, of an Anti-Siphon Trap 
Vent. 

The general plan of trap ventilation is illustrated 
in Fig. 50, which is self-explanatory. 

Where two or more traps, on different floors, are 
connected with one main vent pipe, the latter should 
be connected, obliquely, with the vertical soil or 
waste pipe below the branch pipe from the lowest 
fixture on the stack, so as to remove particles of 
scale and the water of condensation ; and should 
be continued to a point above the roof, or connected 




Fig. 50. 



152 



Traps. 

with the vertical soil or waste pipe above the high- 
est fixture, in manner similar to that shown in Fig. 
22, in a preceding chapter. 

The proper materials and weights 'of vent pipes 
are described in Chapter IV, and too much care 
cannot be exercised in their selection. It is of 
the first importance that the friction due to the 
passage of air through the pipes be reduced to 
the minimum, and that corrosion of the insides of 
the pipes, to any extent, be rendered impossible. 
For these reasons, only pipes of smooth bore and 
of non-corrosive material, or which have been per- 
manently protected against corrosion, should be 
used. Lead comes the nearest to being an ideal 
material for this purpose, and is recommended for 
the branch vents. For the vertical vents, cast iron 
pipes, which have been rendered rust proof, are 
preferred. 

Some idea of the danger to be apprehended from 
rust in a vent pipe may be gathered from the fol- 
lowing extract from "Trap-Siphonage and Trap- 
Seal Protection," by Prof. J. B. Denton: 

"If rust to the thickness of one-hundredth of an 
inch from the internal surface of 10 feet of iy 2 - 
inch vent-pipe should accumulate in an elbow, it 
would more than fill the latter, as it would oc- 
cupy about six cubic inches." (The italics are 
mine. — T. S. A.) 

153 



The Sanitary Sewerage of Buildings. 

The size of vent pipes will depend largely upon 
their length and upon the number of traps which 
they are expected to take care of. 

The usual minimum sizes of back vent pipes, 
i. e., the branch pipes extending from the traps to 
the branch or main vertical vent pipes, are as 
follows : 

i %" pipe for i y^" traps. 

iy 2 " pipe for \y 2 " to 2^" traps. 
2" pipe for 3" to 4" traps. 

There is a certain length of pipe, of each of the 
sizes commonly used for the venting of traps, which 
will protect a trap of a certain size, but these lengths 
can only be determined, with any degree of ac- 
curacy, by experiment, and the known experiments 
along this line are very few, and, in many in- 
stances, unreliable. As previously stated, it has 
been found that 13^ feet of iy 2 " vent pipe, with 
two elbows, will safely protect the seal of a Y^" S 
trap, having only a Ij4" seal, against the greatest 
siphonage influence which can be produced by any 
flow of water in a 2-inch pipe of any practical 
height, even if the waste pipe is closed at the 
top. It has been further demonstrated that the 
friction produced by the passage of air through one 
square iJ/£" elbow is equivalent to the friction pro- 



154 



Traps. 

duced in the same manner by 1.8 feet of pipe of 
the same diameter. These statements cannot, how- 
ever, be taken as indicating the probable necessary 
lengths of vent pipes of the different sizes because 
the conditions in almost every building will be dif- 
ferent. 

In the determination of the sizes governing the 
construction of vent pipes, the same difficulty seems 
to have been experienced as in the determination of 
the sizes of soil and waste pipes, described in Chap- 
ter IV. An analysis of the provisions of the plumb- 
ing codes of twenty-seven of the principal cities in 
the United States reveals the fact that but five of 
the codes have provisions practically alike in re- 
spect to the general sizes of trap vents. There are 
three other groups, of two cities each, in which the 
codes are similar to each other in this particular, 
but different in each case from the codes in any 
other group. The similarity of the codes in any 
two or more cities is due to the copying by one 
city of the code of another city, and not as the 
result of scientific calculations, which, as before 
stated, cannot be made, with any degree of ac- 
curacy, for the various conditions met with in prac- 
tice, except by experiment. Probably the latest 
contribution to the literature upon this subject is 
contained in a table in the new plumbing code of 



155 



The Sanitary Sewerage of Buildings. 

the city of Cleveland, Ohio, of which the following 
is a copy: 

Maximum developed Number 

length in feet. of traps vented. 

Size of pipe. Mains. Branch. Main vertical. 

1 >4 inch vent 10 1 

1 V6 inch vent 20 2 or less 

2 inch vent 40 16 or less 32 or less 

2y 2 inch vent 65 30 or less 60 or less 

3 inch vent 100 60 or less 120 or less 

4 inch vent 150 136 or less 272 or less 

5 inch vent 200 240 or less 480 or less 

6 inch vent 250 360 or less 720 or less 

In the table the following notation of traps and equivalents 

is used : 

Traps 2 inches or less in diameter=l trap. 
Traps 2% inches in diameter=2 traps. 
Traps 3 inches in diameter=3 traps. 
Traps 4 inches in diameter=4 traps. 
Traps over 4 inches in diameter=5 traps. 

If the length of a branch or main vent pipe is to 
exceed the given maximum, the diameters shown 
in the table are to be increased to the tabulated size 
opposite the length required, irrespective of the 
number of traps vented, but in no case are the main 
back vent pipes to be less than one-half the diam- 
eters of the adjoining soil pipes. 

The table has been prepared by men of ability 
and experience in this work, and is probably as 
nearly correct as anything yet published upon this 
subject. 

Objections, valid and otherwise, have been 
made to the use of trap vents, and there is a gen- 
eral tendency toward the adoption of safer and 
less complicated methods of protecting the water 
seals of traps against siphonage and back pres- 
sure. 



156 



Traps. 

As long ago as the year 1886, the late Col. 
George E. Waring, Jr., summarized the prin- 
cipal objections to trap vents in a work on "How 
to Drain a House," from which the following 
extracts are made: 

"While a sufficient vent-hole at the crown of 
a trap will prevent its contents from being with- 
drawn by siphonage (suction), insufficiency in 
such an opening defeats the purpose for which 
it was made. Insufficiency may be due to several 
things : 

(a) The opening may originally be made too 
small. 

(b) It may, and very often does, become 
reduced in size, or entirely closed by the accu- 
mulation of foul matter thrown into it during the 
use of the trap. 

(c) As its efficiency is due entirely to the ad- 
mission of air fast enough to supply the demand 
for air to fill the vacuum caused by water flow- 
ing through some portion of the pipe beyond the 
trap, it is not only a question of having an open- 
ing large enough to admit the air, but of having 
an adequate current led freely to the opening. 

"As the opening is into a portion of the drain- 
age system that is unprotected by a trap, it can- 
not, of course, communicate with the interior 
atmosphere of the house; it must be connected 

157 



The Sanitary Sewerage of Buildings. 

by a pipe either with the open air outside of the 
house, or with the air of the upper part of the 
soil-pipe, above all fixtures. The ability of this 
pipe to transmit air in the volume required de- 
pends on its size and its directness. A one-inch 
pipe, one foot long, for example, may admit air 
fast enough, while a longer pipe of the same di- 
ameter, or a smaller pipe of the same length, 
would not do so. 

"One or other of the defects above indicated 
may very easily defeat the object, and in so far 
as the opening may be decreased by the accu- 
mulation of waste matters, the object which is 
fully secured while the work is new, may be per- 
manently defeated by a condition that occurs 
after a little use. What seemed originally to be 
adequate security may become untrustworthy in 
time." 

Ten years later, in the St. Paul Pioneer Press 
of January 5, 1896, under the caption, "Danger in 
Houses," appeared a copy of the report of W. J. 
Freaney, plumbing- inspector of that city, relative 
to the danger to be apprehended from the use of 
trap vents. While some of the conditions described, 
in the report may not be fully representative of 
plumbing in many other cities, the following ex- 
tracts from the report confirm the statements of 
Col. Waring, quoted above, relative to the non- 
158 



Traps. 

effectiveness of trap vents after they have been 
in use for some time: 

"* * * I have made a somewhat limited ex- 
amination of the practical effect and desirability 
of the present system of so-called trap ventila- 
tion. My investigations confirm the opinion I 
have held for some time, that the crown and 
back-venting of traps, as now practiced, is worse 
than useless. * * * The most serious objec- 
tion, however, to this pernicious custom is the 
sense of false security given to the owner or ten- 
ant of a house provided with so-called modern 
plumbing. 

"I made examinations in twenty-three houses, 
the plumbing work in which was done in the 
very best and most workmanlike manner, all of 
them having been constructed within the last 
seven years, in conformity with the ordinance 
governing plumbing. In twelve of the houses 
examined I found all of the vent pipes from traps 
under kitchen sinks completely stopped by con- 
gealed grease and particles of vegetable matter 
for a space of three inches to a foot above the 
crown of the traps they were supposed to 'ven- 
tilate.' In most cases a strong wire was required 
to dislodge the obstruction. 

"Of the other eleven kitchen sink traps exam- 
ined I found only one that was perfectly clear. 

159 



The Sanitary Sewerage of Buildings. 

* * * In seven of the houses I found a soft 
slimy substance adhering to the interior surface 
of the vent pipes for two or three inches above 
the crown of the traps. While the stoppage 
was not complete, there was every indication 
that an entire obstruction would soon result. 
The remaining three examined were partially 
stopped up ; but in the case of these the vent was 
placed below the crown of the trap and so fash- 
ioned that the lower line followed the descent of 
the waste pipe. I also found that where coup- 
lings were used at the foot of wrought iron vent 
pipes, that the dislodged particles of rust form 
an accumulation sufficient in most cases to stop 
the opening in the bend." 

In the closing paragraph of the report, the in- 
spector calls for the remodeling of the city ordi- 
nance so it shall "conform to modern practice," 
pending which he recommends that publicity be 
given to the subject, so that the people may "take 
individual precautions against the evils in- 
volved." 

Rather more than ten years later, in an ar- 
ticle on "Re-Sealing and Anti-Siphon Traps Ver- 
sus Back Venting,"* H. J. Luff , sanitary engineer, 
Cleveland, Ohio, advanced additional reasons 

* Domestic Engineering, March 2, 1907. 

160 



Traps. 

why the back venting of traps is not absolutely 
reliable : 

"First, back venting, though the greatest care 
may be taken to make the connection to the 
waste pipe in the most approved manner, viz., 
taken off at an angle of 45 degrees beyond the 
crown of the trap, in its installation, is liable to 
be rendered non-efficient from the following 
causes: Where galvanized iron pipe is used the 
galvanizing may form a film which would com- 
pletely stop the pipe. In the use of lead or cast 
iron, the molten metal may enter the pipe 
through the joint when it is being made, and par- 
tially or completely fill it. Oakum placed in the 
pipe to prevent building material from falling 
into it may be forgotten and allowed to remain, 
thus completely stopping the pipe, and if the 
ends of vents are not protected during construc- 
tion, building material may fall into them, and, 
lodging in the elbows, completely stop them. All 
this presupposes carelessness on the part of the 
plumber, but constitutes a factor which cannot 
be ignored, as it too often exists. After the 
vents have been installed, there are conditions 
over which the plumber has no control that oper- 
ate to render the vent pipe non-efficient, viz., the 
freezing of the roof outlets in protracted cold 
weather, the building of nests by the birds, and 
the falling of leaves into roof outlets." 



161 



The Sanitary Sewerage of Buildings. 

After enumerating the danger from clogging 
of the vents by greasy vapor from kitchen sinks, 
he goes on to say : 

"* * * Also, there is the proposition of the 
average plumber clearing the sink waste pipe by 
means of an opening into the waste pipe and 
leaving the vent untouched, or of trying to force 
the obstruction from the waste pipe and forc- 
ing what might be in the vent pipe up against 
an elbow beyond the point of accessibility, or of 
using a blind washer on the back vent union 
and forgetting to take it out. Then there is the 
added danger of piping through which no water 
passes to indicate a leak, should one exist, and 
those of us who have made smoke tests of build- 
ings that have been in use for a few years know 
to what an alarming extent this danger exists ; 
and it is the part of wisdom to reduce it to a 
minimum. 

Eliminating from the objections named those 
which have reference to conditions which might 
result from badly planned work, or from the care- 
lessness of the plumber in the construction of 
the work, or in the removal of stoppages, and 
which should not be advanced as arguments 
against the use of trap vents, we have left the 
one chief objection, viz., the possible stoppage 
of the vents by grease from sinks and by rust 
or scale from the vent pipes. 



162 



Traps. 

The stoppage of vents by grease may, to a con- 
siderable extent, be obviated, and the removal of 
such stoppages, should they occur, be rendered 
easy, by the connection of the vent with the trap 
in the manner shown at A, Figure 51. The 



\ 


Q\ 


f 


•p 


\ 


a 




I 


( 


\ 


<s 





Fig. 51. 

usual, and very objectionable, method is to place 
the vent at the crown of the trap, as shown at B, 
in the figure. 

There are many locations where a long line of 
vent pipe may be dispensed with, notably where 
the trap to be vented is on a lower floor, by the 
use of what is known as an anti-siphon trap vent, 
a sectional view of which is shown in Figure 52. 



163 



The Sanitary Sewerage of Buildings. 

The cup "B" is lifted by the air pressure against 
its under surface, and admitting a free inflow of 
air, as indicated by the arrows. As soon as the 
demand for air is satisfied, and the equality of 
pressure re-established between the air of the 
room and the air of the pipe, the cup will drop 
back, by gravity, into the mercury seal L. 




For some reason not stated, the use of this 
form of trap vent is prohibited by the plumbing 
codes of some cities in the United States. It has 
stood the test of years, and has been endorsed by 
many prominent engineers, among whom may 
be mentioned the late Col. George E. Waring, 
Jr., and is a much better method of preventing 
siphonage in traps than the more expensive and 
uncertain vent pipes extended above the roofs; 
but, as will be seen by a study of its construc- 



164 



Traps. 

tion, it would be useless as a preventive of seri- 
ous back pressure. As a rule, one large sized 
trap vent of this kind may be made to protect the 
seals of all the traps in an ordinary toilet room. 

Where it is preferred to sacrifice the self- 
cleansing properties of a trap for the purpose of 
securing safety against siphonage without the 
use of trap vents of any kind, and there is a 
growing tendency in this direction, anti-siphon 
or, as they are often termed, re-sealing traps 
may be used for all fixtures other than water 
closets and slop sinks. 

In the absence of reliable tests, the conditions 
under which the various traps for which non- 
siphoning qualities are claimed may or may not 
be used, without back venting, with absolute 
safety against siphonage, will be, largely, a mat- 
ter of conjecture. The only tests, of an official 
nature, of which we have knowledge, are those 
prescribed in the Cleveland plumbing code. The 
tests are arranged in three classes : 

i. For re-sealing traps, the developed length 
of the waste pipes which are not more than 
five feet, measured from the traps to the 
horizontal soil or waste pipe branches of circuit 
or loop systems. 

2. For re-sealing traps, located horizontally 
or vertically, not to exceed ten feet from a soil 
or waste pipe stack or house drain. 



165 



The Sanitary Sewerage of Buildings. 

3. For anti-siphon traps, located horizontally 
or vertically, not to exceed ten feet from a soil 
or waste pipe stack or house drain. 

For class one (1), a bell shaped tank is to be 
used, with a capacity equal to the cubical con- 
tents of eight feet of pipe of the same diameter as 
the trap to be tested. The tank is to have a five 
foot vertical arm, and when the contents of the 
tank has been discharged through the trap, the 
depth of seal retained shall not be less than the 
one and one-quarter inch seal in a plain trap. 

For class two (2), the same kind of apparatus 
is specified as for class one (1), but the capacity 
of the tank is to be equal to the cubical contents of 
thirteen feet of pipe of the same diameter as the 
trap to be tested, and the vertical arm is to be ten 
feet. After the test, the seal retained shall not be 
less than the two and one-half inches seal in a plain 
trap. 

For class three (3), a fifty gallon tank is to be 
placed ten feet above the trap connection, and the 
trap connected, by a Y connection, to a vertical pipe 
no smaller than the trap outlet and forty feet long 
over all. The entire contents of the tank is to be 
discharged through the vertical pipe, by the open- 
ing of a quick opening valve every five seconds, aft- 
er which test the seal retained shall not be less than 
one inch in depth, and the volume of water not less 
than two and one-half inches seal in a plain trap. 



166 



Traps. 




_1 



¥ 



Fig. 53. 



A suitable apparatus 
for this test is shown 
in Figure 53, the cut 
for which was kindly 
furnished by the pub- 
lishers of "Modern 
Sanitation." 

It is to be regretted 
that the code under 
consideration was not 
so framed as to place 
the re-sealing and an- 
ti-siphon traps in one 
class, under the gen- 
eral title of anti-si- 
phon traps, and to 
provide one standard 
test for all such traps, 
because a multiplicity 
of standards must 
lead to confusion, and 
necessitates the carry- 
ing in stock, by the 
dealers in plumbing 
goods, of different 
kinds of traps for the 
different conditions 
under which they may 
be used. 



167 



CHAPTER VIII. ,, 

Final Test and Inspection — Subsequent Test 
and Inspection, Official and Unofficial. 

T^INAL Test and Inspection. — In localities hav- 
■*• ing up-to-date plumbing codes, a final test and 
an official inspection will be required at the comple- 
tion of the work. 

In localities where plumbing work is not under 
local supervision, a final test of the work should be 
insisted upon by the owner of the building, and 
should be carried out under the supervision of some 
person familiar with but not directly interested in 
such work. 

It should be a matter of pride with every plumber 
to execute his work in such a manner that it will 
stand any and every test which may be required. 
Such work cannot fail to commend itself and secure 
an increasing and continued patronage. 

There are two ways in which the final test may be 
made: 

i. By the peppermint test. 

2. By the smoke test. 

The peppermint test is made by pouring into one 
or more soil pipe extensions on the roof a quantity 
of oil (not essence) of peppermint, varying in 
amount from two to five ounces, according to the 



168 



Tests and Inspections. 

amount of piping to be tested, followed by a small 
pailful of very hot water, the fresh-air opening and 
all other untrapped openings in the pipes having 
previously been tightly closed. The openings into 
which the peppermint was poured should then be 
tightly closed, and the person who handles the pep- 
permint should remain on the roof until sufficient 
time has elapsed to enable someone to go through 
every part of the building to ascertain if there is any 
odor of peppermint and to locate possible leaks. 
Toilet rooms on the upper floors should be first 
visited, and from thence the course should be down- 
ward, through the toilet rooms, kitchen, and pantry 
(if it contains a sink), on the lower floors, finishing 
in the basement. The bottle containing the pepper- 
mint should not be carried through any part of the 
house; and, while the test is being made, all win- 
dows, and all doors, both inside and outside, should 
be kept closed. It is scarcely necessary to state that 
fixtures should not be flushed at any time during the 
test. If hot water is laid on to the fixtures, the 
volatilization of the peppermint will be more com- 
plete if the soil and waste pipes are warmed up by 
running hot water through them for a short time 
prior to the insertion of the peppermint. 

The principal objection to the peppermint test is 
that, owing to the rapid diffusion of peppermint in a 
room into which it may escape, the location of the 
leak will usually be difficult, and recourse must then 



169 



The Sanitary Sewerage of Buildings. 

be had to the smoke test. It would therefore be better 
to make use of the smoke test, whenever this can be 
done, and the piping is not so concealed as to render 
impossible the escape of smoke from possible defects 
into the building. 

. The smoke test is usually made by forcing into the 
sewer the smoke from burning oily waste, and some- 
times from tar paper and oakum, under a pressure of 
not more than one inch of water column. Many 
forms of machines for this purpose are on the mar- 
ket, one of the best of which is shown in Figure 30, 
Chapter V. In making the test, the smoke should 
preferably be pumped into the sewer at the fresh-air 
opening, but where this is not practicable, it may be 
pumped into the extension of a soil pipe on the roof, 
provided a level spot can be found on which to place 
the machine. All pipes on the roof, and all other 
openings in the sewer, excepting that to which the 
smoke machine is attached, should be left open until 
smoke escapes from them in quantity, and then be 
tightly closed. Doors and windows in the vicinity 
of the smoke machine should be closed during the 
test. When the floating drum of the smoke machine 
shows the sewerage system to be full of smoke, and 
under the required pressure, the pumping should be 
stopped, the drum watched for from five to twenty 
minutes, according to the extent of the work to be 
tested, and the entire system inspected for possible 
smoke leaks, through defects in the materials or 

170 



Tests and Inspections. 

joints or through traps which have not sufficient 
water seals. If, at the expiration of the time stated, 
the drum continues to float at the same height, and 
there is no appearance of smoke escaping from the 
pipes, etc., at any point, the work may be considered 
satisfactory. 

If the final test is made under the supervision of a 
plumbing inspector, he will usually make a thorough 
inspection of the completed work at this time, not- 
ing, particularly, the kind of traps used ; the methods 
of connecting the traps with the branch pipes; the 
sufficiency, or otherwise, of the measures taken for 
the prevention of the loss of seal in traps ; the 
methods of connecting the back vents with the traps 
and with the main vent pipes; and any other details 
which may not have been ready for inspection at the 
time the roughing-in test and the preliminary in- 
spection were made. 

Subsequent Test and Inspection, Official and Un- 
official. — Unless complaint is made relative to the 
insanitary condition of the sewerage of a building, 
or there is reason to suspect the sewerage of any 
building as the source of an outbreak of a dangerous 
disease, official tests and inspections of the sewerage 
of buildings, other than those made at the time of 
construction or reconstruction of the sewers, will 
not, usually, be made. 

Wherever carried out, regular or occasional tests 
and inspections of the sewerage of buildings have 

171 



The Sanitary Sewerage of Buildings. 

been productive of much good, but the cost of mak- 
ing such inspections upon an extensive scale would 
probably be considered a serious objection from the 
standpoint of the taxpayer. There are, however, 
certain classes of buildings which should receive at 
least one visit each year by an inspector, acting 
under the direction of the health department of every 
locality which has a public water supply and a sys- 
tem of sewers, viz. : public buildings, tenement 
houses, the older classes of buildings, buildings in 
the congested portions of cities, hotels, restaurants, 
bakehouses, factories and buildings of every descrip- 
tion where the sewerage would be subject to rough 
or improper usage or neglect. 

The failure of local health authorities to make 
periodical inspections of the sewerage of buildings 
in any locality does not, however, relieve the owners 
of buildings of personal responsibility in the matter. 
It is not expected, however, that every owner of a 
building will be competent to make tests and inspec- 
tions of the sewerage, and to pass judgment upon its 
condition from a sanitary standpoint. This work 
should be done by a competent and reliable plumber, 
or, better still, by a sanitary engineer who is not 
directly interested in any plumbing business in the 
locality. 

A marked improvement in the condition of the 
sewerage of buildings would result from a demand, 
by every prospective tenant of a building, for the 



m 



Tests and Inspections. 

production, by the owner, of a certificate, or other 
statement in writing, that the sewerage of the build- 
ing was in a sanitary condition at the time of letting. 
Notwithstanding that the sewerage of a building 
was originally well planned and constructed, build- 
ings will settle and possibly result in fractures in the 
sewer pipes; alternate expansion and contraction of 
the vertical soil and waste pipes may result in defec- 
tive joints in the branches, which are usually con- 
cealed; vent pipes may become clogged to such an 
extent as to render them ineffective, or nearly so; 
and yet many owners of buildings seemingly act 
upon the presumption that the sewerage of their 
buildings is in proper condition until a defect may be 
accidentally revealed, or a stoppage takes place in 
some part of the system, causing inconvenience. 



173 



CHAPTER IX. 

The Disposal of Sewage in Unsewered 
Localities. 

TN the smaller cities, and in many villages, the 
mistake is frequently made of insta ling a public 
water supply without any provision for the removal 
of sewage and waste water, and as a n suit the in- 
habitants are compelled to resort to the i se of cess- 
pools, thus endangering the water in the private 
wells — of which there are usually quite a number 
— and creating an unwholesome condition of the 
subsoil in the immediate vicinity of buildings. Such 
a condition is inexcusable, yet is often permitted to 
continue for years, and as soon as one cesspool re- 
fuses longer to do its work another is dug, until 
the ground is often honeycombed with these pestif- 
erous pits. 

In some such localities advantage is sometimes 
taken of a system of storm drains for the disposal 
of sewage, with the result that stoppages are fre- 
quent and the subsoil is seriously contaminated by 
leakages through imperfect joints. 

In other such localities, where a natural water- 
course is within easy distance, the sewers of many 
buildings are made to discharge, individually or 
collectively, into what in dry weather may be but 



174 



Disposal of Sewage:. 

a trickling stream, resulting in a foul condition of 
the bed of the watercourse for a considerable dis- 
tance. Even where the flow of water is sufficient 
to effect a considerable dilution of the sewage and 
its removal without offense to the senses of sight 
and smell, the practice of discharging crude and 
often infected sewage into a natural watercourse, 
which may be used for the watering of stock or as 
a source of water supply for some other locality, 
is reprehensible and should be prohibited by law. 

A very dangerous, though not very common, 
practice is the discharge of the sewage of isolated 
buildings into wells which have become dry or unfit 
for use as sources of water supply, or into deep bor- 
ings in the subsoil. In either case the under- 
ground streams of water from which the water 
supplies of other buildings might be obtained would 
be in serious danger of contamination and infec- 
tion. 

For isolated buildings, where a public sewer is 
not available for an outlet, the sewage may be dis- 
posed of in a sanitary manner : 

1. By irrigation. 

2. By the use of a septic tank, with or without 
subsequent filtration. 

Irrigation, as applied to sewage disposal, may 
be divided into two principal classes, viz., surface 
and sub-surface. 



175 



The Sanitary Sewerage of Buildings, 

Surface irrigation, as its name implies, consists 
in the discharge of sewage on the surface of the 
ground, necessarily at some considerable distance 
from occupied buildings and from any well or 
other source of domestic water supply, For the 
proper working of this method of disposal the 
land to be irrigated should be comparatively dry and 
porous in character, and in area sufficient to provide 
for two or more beds, of equal size, so that the sew- 
age may be diverted from one bed to another at fre- 
quent intervals to allow the land last irrigated to 
rest and regain its normal condition. The beds 
should be level and banked with earth on the out- 
side so that they may be flooded to an equal depth. 
To accomplish the uniform flooding of every por- 
tion of the beds the sewage should be delivered in 
quantity and within a short space of time. This 
would necessitate ihe collection and storage of sew- 
age at some point above the bed, and its sudden lib- 
eration at stated intervals into the sewer leading to 
the beds. As any arrangement for this purpose 
which depends upon personal attention would be 
very likely to be forgotten at some time or other, 
an automatic flushing tank should be installed in 
the line of the main sewer, at a point where it can- 
not become a source of offense to any person, and 
placed at such a depth as will render freezing of 
the contents impossible. 



176 



Disposal of Sewage. 

Where a considerable quantity of sewage is to 
be disposed of in this manner, to prevent satura- 
tion of the subsoil it will usually be necessary to 
place under-drains, made of common field tile, be- 
neath the irrigation beds, at a depth of from four to 
six feet beneath the surface of the ground, and with 
an outlet into a ditch or other watercourse. 

In sewage disposal plants of this character it is 
customary to effect the separation of the bulky 
solids from the sewage by a grating, usually in the 
collecting and storage chamber, from whence they 
are removed by hand and spread on or spaded into 
the ground. 

While the cropping of the irrigation areas is 
not necessary to the purification of the sewage, 
vegetation will use up a large portion of the avail- 
able organic matter and a considerable amount of 
water; will relieve the beds of much of the work 
they would otherwise have to perform, and, in the 
case of large areas, might be made to yield a fair 
return for the labor involved. 

Where properly planned and cared for, sewage 
plants of this character should not be a source of 
danger or offense to any person, and will accom- 
plish the purification of the sewage with the mini- 
mum of expense both for installation and mainte- 
nance. 

Sub-surface irrigation, which is also known as 
"intermittent downward filtration," does not differ 



177 



The Sanitary Sewerage of Buildings. 



materially from irrigation proper save in the man- 
ner of applying the sewage to the land and in the 



» a 



,t> 






~\ ~ — ~ I 7~ 



\ 



/© 



,t> 



I 



h 



-i- 



I i i 

Is ': / 

/ I I 

1 1— 



—I 7 

/ / 

/ / 

/ 



/ " / 



«p 



JZniet 
Fig. 54. 

greater depth at which purification may be accom- 
plished! In surface irrigation the purification of 



178 



Disposal op Sewage. 

the sewage is said to be effected by aerobic or nitri- 
fying bacteria, which swarm in innumerable myriads 
near to the surface of the earth ; while in sub- 
surface irrigation, with a porous soil and frefe un- 
der-drainage, the depth at which the bacteria may 
be induced to perform their functions will be lim- 
ited only by the depth of the under-drains. By in- 
creasing the depth of the purification beds we may 
limit their surface area — a very important consid- 
eration where land is expensive or limited in 
amount. 

The general plan of a sub-surface irrigation bed 
is : shown in Figure 54. 

The main feeder A may be constructed of al- 
most any kind of earthenware pipes, providing the 
joints of same can be made watertight. They 
should usually be 4 inches in diameter and have a 
fall of about 1 to 1^ inches in 50 feet. 

The branch feeders B should be of porous field 
tile, 2 inches in diameter, and laid at about 8 inches 
below the surface of the beds at their highest 
points. The capacity of the feeders need not be 
greater than that of the storage tank, measured by 
the space occupied by the sewage just before its 
discharge into the feeders. The joints of the branch 
feeders should be open, i. e.> the ends of the pipes 
should be about l /\. inch apart, and the upper part 
of the opening thus formed should be covered with 



179 



The Sanitary Sewerage of Buildings. 

some imperishable material to prevent dirt from 
falling into the pipes. 

For the purpose of maintaining the proper grade 
and alignment of the main and branch feeders both 
sets of pipes should be laid on a board or other 
suitable foundation. 

In order that the main feeder may be entirely 
emptied by the branches the inverts of both sets of 
pipes should be on a level, to accomplish which 
specially designed branch pieces should be used. 
Where the latter cannot readily be obtained a num- 
ber of perforations in the bottom of the main feed- 
ers may be made to serve the purpose. 

The main and branch under-drains, shown by 
the dotted lines C and D, may be of similar mate- 
rials and of the same general construction as the 
feeders, save that they need not usually be laid on 
an artificial foundation. The branch drains should 
have a gradual fall toward the main drain, and the 
fall of the latter will be regulated by the difference 
between its depth near the bed and at its outfall. 
The main drain may be laid immediately under and 
parallel to the main feeder, or at right angles to 
the same, as shown in the figure. 

In the event of a stoppage in the feeders it will 
be necessary to take up the branch feeders, but the 
main need not be disturbed if clean-outs are 
provided at the points E and F. The clean-out F 
should be provided with a tight-fitting stopper, but 



180 



Disposal of Sewage. 

the clean-out E should be kept open at all times to 
assist in the aeration of the beds. As grease is one 
of the most common causes of stoppage in such 
plants, it should not be allowed to pass into the 
sewer, but should be intercepted by a grease trap, 
an illustration of a good form of which may be 
found in a preceding chapter. 

Where only the waste water from a sink is to be 
taken care of, under favorable conditions the auto- 
matic flushing tank and the under-drains may be 
dispensed with, and a single line of sewer, with open 
joints at its lower end, would usually be sufficient 
to properly dispose of the same. 

LEACHING CESSPOOLS. 

Notwithstanding that much has been written up- 
on this subject, there is still a somewhat prevalent 
misunderstanding relative to the inefficiency of and 
the danger to be apprehended from the disposal of 
sewage by means of leaching cesspools. That this 
is so, is evidenced by the fact that the boards of 
health of some localities endorse their use, sub- 
ject to certain restrictions, as a makeshift method 
for disposing of the sewage of the unsewered por- 
tions of such localities. 

A leaching cesspool, built in a sandy or other 
porous formation, will usually take care of the 
sewage from a dwelling, in many instances for an 
indefinite period, but, under the best conditions, 



181 



The Sanitary Sewerage of Buildings. 

this method of disposal cannot be considered sani- 
tary and for the following reasons : 

i. The leakage of sewage into the subsoil would 
be very variable, both as to time and amount, and 
the regular periods of rest, so essential for the 
proper working of any filtration (oxygenation) 
area, could not be secured. 

2. The leakage of sewage from the cesspool 
would take place at a considerable distance below 
the surface x>f the ground, and would thus render 
the access to that portion of the subsoil of the 
proper amount of oxygen for the maintenance of 
the nitrifying (aerobic) bacteria practically impos- 
sible. 

3. A lack of oxygenation of the sewage would 
result in the deposition of organic impurities in 
the interstices of the soil and this, in turn, in the 
creation of an unwholesome condition in the vicin- 
ity of the cesspool and, possibly, in the clogging of 
the voids in the soil. 

4. Notwithstanding that a leaching cesspool may 
be located at what may be considered a safe dis- 
tance from a well, there is always a possibility of 
the unpurified, and possibly infected, sewage find- 
ing its way into and contaminating an underground 
body of water from which wells, even at a consider- 
able distance, derive their supplies. 

The expense which would be incurred in the con- 
struction of sewers in the outlying and sparsely set^ 



182 



Disposal of Sewage. 

tied portions of many cities and villages would be 
very considerable and would operate to prevent the 
adoption of any such measures for the relief of the 
inhabitants thereof. Hence, resort is usually had 
to cesspools, and in some cities tight and leaching 
cesspools are used in combination. To properly 
construct these receptacles, especially where used in 
combination, as mentioned above, would entail no 
small expense, and, in many instances, the money 
expended for such expedients would go a long way 
toward defraying the cost of sanitary sewers. 

THE SEPTIC TANK METHOD OF DISPOSAL. 

Up to within a short time ago, the use of septic 
tanks was confined, almost exclusively, to the dis- 
posal of the sewage of cities and large villages, 
and of buildings of a public or quasi public char- 
acter. In many parts of the country, they are 
now being used and installed for the disposal of 
the sewage of isolated dwellings, and, it is 
claimed, with much success. 

Although the septic tank method of disposal is 
yet in the experimental stage, in its present im- 
perfect condition, it is vastly superior to any other 
method yet devised, and there are no apparent 
reasons why this method, which has been suc- 
cessfully used in many parts of this country arid 
in Europe, for the disposal of sewage on a large 
scale, should not, subject to proper control, be 



183 



The Sanitary Sewerage of Buildings. 



provided with cleanout openings above the water 
universally adopted for 
the disposal of the sew- 
age of isolated dwellings. 

The success, or failure, 
of a septic tank will 
depend, to a consid-JT 
erable extent, upon 
the correctness, or 
otherwise, of its design 
and, for this reason, the 
construction of such tanks 
should not be attempted 
without the aid of plans 
prepared by an engineer 
who has had much experi- 
ence in this line of work. 

The component parts of 
a purification plant of this 
character are : 

i. A septic tank, for 
the liquefaction and gasi- 
fication of the solid matters in the sewage which 
can be so reduced. 

2. A filtration area, for the nitrification (oxi- 
dation) of the organic constituents in the liquid 
sewage. 

In the treatment of sewage by this process on a 
large scale, it is customary to install a settling 




184 



Disposal of Sewage. 

basin for the removal of the coarser constituents 
of the sewage before it enters the septic tank. In 
the disposal of the sewage of a single dwelling, 




TAtiK 



r ai 



in 

^fc ow/v/mg ro suArACf 

1 /'Off /u# tmes 






<§^§t<sinsi of drains lite for Sub -soil [Inrocjolfm ~ 

Fig. 56. 

however, if the outlets of the sinks, bath tubs, and 
wash basins are properly protected by strainers , 
the cellar drains provided with proper gratings and 
silt chambers , and proper care is exercised in the 



185 



The Sanitary Sewerage of Buildings. 

discharge of slops into water-closets, there would 
be little, if any, need for this weeding out process. 

Examples of domestic septic tanks in general 
use in certain sections of this country are shown 
in Figures 55, 56 and 57. 

The tank shown in Figure 55 is of cast iron, is 
circular in cross-section and has an internal parti- 
tion, or baffle, around which the sewage must travel 
ill its passage through the tank. The effluent from 
this type of tank is usually discharged into an 
underground filter, termed a "Nitrification Duct." 

The types of tank and irrigation pipes shown in 
Figures 56 and 57, the cuts for which were pre- 
pared by Herbert F. Shade, Plumbing Inspector, 
Victoria, B. C, have been used quite extensively in 
the locality just named. The cuts are nearly self- 
explanatory. It should be explained, however, that 
the by-pass in the sewer, extending over the tank, 
shown in Figure 56, is for the purpose of encour- 
aging a draft down the openings and through the 
tile drain, thus aerating the sewage. It should also 
be explained that the partitions in the tank, shown 
in Figure 57, are for the purpose of insuring proper 
septic action with small as well as large quantities 
of sewage. The size of the tank is based upon a 
daily consumption of water equal to forty gallons 
per person and is 12x4x6 feet in dimensions. The 
first compartment is capable of treating the sew- 
age of ten persons, and when this amount is ex- 

186 



Disposal of Sewage. 



ceeded, the sewage would pass under the first di- 
visional board to the next compartment, and so on. 



am inter 




<GQ£<S>&,§> S 




■SCALC-?/H - /roor- 



Fig. 57. 



Mr. Shade states that he has personally supervised 
the construction of at least two hundred of such 



187 



The Sanitary Sewerage of Buildings. 

tanks and that he has yet to hear the first complaint 
of their not working satisfactorily. 

The forms of septic tanks shown in Figures 55 
and 56 do not provide for the intermittent discharge 
into the subsoil drains of the septicized sewage; 
hence, the sewage will usually pass out of the tanks 
in small quantities and at very irregular periods, 
and will not reach every part of the filtration areas, 
except at such times as there may be a considerable 
discharge from the house fixtures. The addition 
to such tanks of automatic flushing chambers, by 
which definite quantities of sewage would be dis- 
charged at regular and not too frequent intervals, 
would be a great improvement and would afford 
the filtration areas the periods of rest so essential 
to their proper working. 

As before stated, the septic tank method of sew- 
age purification is yet in the experimental stage, and 
it is claimed that, with this method of purification, 
it is difficult to obtain an effluent free from disease- 
breeding germs. For this reason, great care should 
be exercised in the location and construction of such 
plants, and it is safe to say that they should never 
be located where the effluents could readily perco- 
late to underground bodies of water from which 
domestic supplies are or may be obtained. For the 
same reason, conclusions relative to the amount of 
purification effected by any such plants can only 
be drawn, with any degree of accuracy, after re- 



188 



Disposal of Sewage. 

peated chemical and bacteriological tests of the final 
effluents have been made. Where the effluent from 
a septic tank is discharged into leaching pipes be- 
low the surface of the ground, as in Figure 56, the 
determination of the purity of the effluent from the 
pipes will be a matter of conjecture. 

Where a septic tank is used, the main trap may 
be omitted, and the air inlet may be placed in the 
sewer near to and on the house side of the tank. 

With any method of treatment of sewage, to ob- 
viate pumping of the sewage, a natural slope of 
the land towards the outfall of the sewer will be 
necessary. Except in the case of large buildings, 
where expense might not be a serious considera- 
tion, the raising of the sewage from one level to 
another would be out of the question. 

If the outfall of a purification plant is into a 
natural watercourse, to prevent interference with 
the working of the plant and the probable flooding 
of the filtration area, the invert of the main drain, 
at the point of outfall, should be above the high 
water mark of the watercourse. 

To reduce the quantity of sewage to be purified 
to the minimum, wherever possible, the rain and 
surface water should be excluded from the sewers 
leading to the filtration plants. 



189 



CHAPTER X. 

The Care of Private Sewers — Responsibilities 
of Owners and Occupiers of Buildings. 

A S PREVIOUSLY indicated, the sewerage of a 
building may be well planned and construct- 
ed, and the owner of the building thereby filled 
with a sense of security against the common dan- 
gers and tribulations incident to house sewerage, 
yet, from the time the sewer and its adjuncts are 
first used, the seeds of trouble will be ever present 
and they will remain dormant only so long as the 
conditions are not favorable to their growth. 

THE SOUNDNESS OF SEWERS — RESPONSIBILITY OF 
OWNER. 

The responsibility for the maintenance of a sound 
condition of the sewerage of a building, in so far 
as relates to fractures in the pipes or to defective 
joints, resulting from a settlement of the building or 
from the alternate expansion and contraction of the 
pipes, should, very properly, rest with the house 
owner. 

For the purpose of ascertaining what, if any, 
defects may have occurred in the sewerage of a 
building since its installation, particularly at the ex- 
piration of the first twelve months, when the build- 



190 



Care of Private Sewers. 

ing will have ceased to settle, a peppermint test 
should be carried out by, or at the expense of the 
owner, in the manner described in Chapter VII., 
and this test should be repeated annually. 

THE PROPER WORKING OF SEWERS RESPONSIBILITY 

OF OCCUPIER. 

The responsibility for the proper working- of the 
sewerage system of a building will, to a great ex- 
tent, rest with the occupier. This implies, princi- 
pally, a two-fold duty, viz. : 

i. The prevention of the entrance to the sewer 
of such solid matter as would tend to stoppages 
in the sewer; and, 

2. The maintenance of the normal level of the 
water seals of all traps. 

Where a sewer is well constructed, the several 
openings to the sewer well protected by strainers, 
and proper care exercised in the discharge of slops 
into water closets, and of greasy water into sinks, 
the possibility of the accumulation of solid mat- 
ter in the sewer to such an extent as to cause a 
stoppage will be very remote. 

Where the outlets of the several plumbing fix- 
tures, and the surface openings in the floors of 
basements, toilet rooms, etc., are properly trapped, 
and the traps protected against loss of seal by siphon- 
age, back pressure, or evaporation, the possibility 



191 



The Sanitary Sewerage of Buildings. 

of sewer air entering the building at these openings 
will be slight. 

In ordinary dwellings, the care of the sewerage 
should not be difficult, and the exteriors and visi- 
ble surfaces of the plumbing fixtures will often be 
found to be all that could be desired in point of 
cleanliness, but, on examination, there will fre- 
quently be found a very foul condition of the traps 
and, in the case of cellar drains, a considerable re- 
duction of the water seals, or an entire absence of 
water in the various devices for preventing the en- 
trance to the buildings of sewer air at such points. 

Care of traps. — A periodical examination and 
cleansing of the fixture, refrigerator and floor traps, 
and the occasional discharge into the floor drains 
of a pailful of water, would, ordinarily, serve to 
maintain the sewerage of a building in a sanitary 
condition for a long time. 

Where the traps in a building are numerous, and 
in any case where the person responsible for the 
care of the plumbing is not familiar with such work, 
the taking apart and replacing of the trap screws 
should be done by a plumber. This is particularly 
important in the case of traps of large diameter and 
provided with clean out openings above the water 
seals, as the improper closing of such openings 
might result in the leakage of water or in the pas- 
sage of air from the sewer to the interior of the 
building. 



192 



Care of Private Sewers, 

In buildings of a public, or quasi public, char- 
acter ; in hotels ; in residence buildings occupied by 
many persons, as tenements ; and in any building 
where the plumbing fixtures and accessories would 
be liable to rough or improper usage, the care., of 
the sewerage will be no small task, and will require 
regular and systematic attention. Nevertheless, 
these are the very classes of buildings in which such 
work will, usually, be neglected until some fixture, 
trap, or other portion of the sewerage system ceases 
to perform its proper function. 

Placarding in Toilet Rooms. — In these days of 
enlightenment, the placarding of the walls of a toilet 
room with notices for the guidance of the uninitiated 
or the restraint of careless persons who make use 
of the room, would seem to be unnecesary, yet this 
plan would prove to be a good educator and would 
often save considerable trouble as the result of stop- 
pages. The following are suggested as suitable for 
the placarding of walls in the vicinity of wash basins 
and water closets : 



TO USERS OF THIS WASH BASIN. 

Hair, lint, matches, or any other solid 
substance, should not be put into the 
basin, as they tend to stoppages in the 
trap or in some other part of the sewer- 
age system. 



193 



The Sanitary Sewerage of Buildings. 



TO USERS OF THIS WATER 
CLOSET. 

Matches, Apple Cores or Parings, 
pieces of hard paper, cloths, or any 
other foreign substance, should not be 
thrown into the bowl as they tend to 
stoppages in the trap or in some other 
part of the sewerage system. 



Grease Traps. — In buildings where grease traps 
are used, they should be cleaned out as often as a 
considerable scum forms upon the surface of the 
water in the traps. Where no grease trap has been 
provided, very greasy water should not be thrown 
in the sink, but should be thrown on a piece of 
land, if the same is available, and not too often in 
the same place. Occasional spading of the land 
where such slops are thrown would be advisable. 

Flushing of Servers. — Where a sewer has not a 
sufficient fall and a flushing tank has been provided 
for the purpose of keeping the sewer free from de- 
posits, the tank should be examined frequently to 
ascertain whether it is performing its proper func- 
tion. Where no special means of flushing are pro- 
vided for such a sewer, and there is a trap in the 
floor of a basement room, a powerful stream of 
water, from a hose inserted in the trap at least once 



194 



Care op Private Sewers. 

in each week, would be of considerable service in 
keeping the sewer clean. 

Air Inlets. — When placed on a level with or but 
slightly above the surface of the ground, the air 
inlets of sewers may become defective, or choked 
with dirt, leaves, snow, etc., and they should be ex- 
amined at frequent intervals to ascertain whether 
they are in working order. 

Purification Plants. — In the case of buildings not 
connected with a public sewer, but which are pro- 
vided with purification plants, the latter should re- 
ceive frequent and regular inspection, with special 
reference to the rapidity with which the sewage 
is escaping from the filtration areas. If sewage re- 
mains for any length of time in the drains from 
which it is supposed to leach into the filtering me- 
dium, — as can be ascertained by means of the grade 
openings provided for the ingress of air to the 
drains — clogging of the pores of the filtering me- 
dium would be indicated. 

Sezverage in Unoccupied Buildings. — There are 
two principal dangers to be apprehended from the 
sewerage of unoccupied buildings, viz., in the mild 
and warm weather, the evaporation of the water 
seals of fixtures and floor drains, and, in winter, the 
freezing of the water in the several traps. For the 
prevention of the evaporation of the water seals, 
oil, of one of the heavier, non-drying kinds, should 
be carefully poured into the traps, in quantity suffi- 

195 



The Sanitary Sewerage of Buildings. 

cient to form a thick layer on the water ; or, if the 
building is to be vacant for a considerable time, the 
water may be removed and the trap filled with the 
oil. The latter method will also be suitable for the 
protection of the traps of such buildings during 
freezing weather. When the buildings are again 
occupied, the oil should not be allowed to enter the 
sewer, but should be carefully removed from the 
traps and the traps cleansed with a hot solution of 
common soda, or other suitable alkali. 



196 



INDEX 

Page. 

Accessibility of sewer, importance of 52 

Access openings for inside sewers, where placed 57 

Advantage of private vent pipes connected direct to 

sewer 47 

Air inlet, care of by occupant' of building 195 

for main trap 45 

location of 51 

Air lock between sink and grease interceptor, to 

prevent 100 

Amount of water necessary for domestic purposes.. 27 
Anti -siphon trap vent, experiments relating to.. 142-143 

Apparatus for testing roughing-in work. 86-91 

Apartment building, size of soil pipe fbr 69 

Approximate inclination of sewers 28 

Arrangement of toilet room 130 

Back pressure influence on fixture traps 145 

may destroy seal protected by vent pipe 148 

on fixture traps, causes of 146 

on fixture traps, to prevent 147 

Back venting of traps, not absolutely reliable 161 

Back vent pipes, minimum sizes of .154 

Baths, shower 127 

Bath tubs, size of waste pipe for 112 

"Bell" trap, why unsatisfactory 59 

Branch pipes, proper connection with vertical stacks. 83 
Branch waste pipes, access openings where neces- 
sary 84 

under floors not desirable 84 

Brass pipe, defects of 68 

where used 68 

Calculation of rainfall 30 

Capillary attraction, loss of water seal by 151 

Care of air inlets by occupant of building 195 

private sewers 190 

purification plants 195 

traps by occupant of building 192 

Cast iron, qualification of, for fixtures 93 

199 



Page. 
Catch-basin and trap, for removal of surface water.. 60 

for floor of toilet, rooms 60 

Cellar fixtures 95 

Cement for joints of earthenware sewers 39 

Cesspools, dangers of 174-182 

leaching- 181 

Cistern waste and overflow, disposition of 65 

Cleaning- sewers, provisions for 53 

Clean-out for fixture traps 136 

construction of 57 

Clean-out plugs, concealed 58 

Closet discharge capacity of various sized sewers.... 71 
Closets, trough 116 

why inferior 117-118 

Concealed clean-out plugs 58 

Connection for brick sewer 36 

earthenware sewer 36 

Considerations governing construction of sanitary 

sewers 13 

Construction of beds for sub-surface irrigation sew- 
age disposal 179-180-181 

beds for surface irrigation sewage disposal. . 176-177 

main trap without manhole 49-50 

Copper, where and how used 94 

Corrosion, how to protect iron sewer pipes from 23 

Cropping sewage irrigation beds, benefit of 177 

Curves or bends, reasons why objectionable 19 

Curves, proper and improper method of making 19 

Decomposition of sewage, when it should take place. 13 
Deductions from experiments on trap siphonage .. 140-141 

Depth of private sewers 32 

Disinfection of dejecta, importance of 15 

Disposal of sewage in unsewered localities 174 

Dissemination of infection through sewers 15 

Drains, floor 58 

Durability of sewer materials essential 17 

Earthenware pipes for sewers, necessary qualities of. 24 
Earthenware sewers, objections to 21 

when preferred 22 

lasting qualities of 22 

and iron sewers, qualifications compared 23 

Evaporation in traps, loss per day by 150 

Evaporation of water from trap, rapidity of .... 149-150 
Even bearing for sewer' pipes, importance of 38 

200 



Page 
Extension above roof of soil, waste, and vent pipes. .76-77 

of two soil pipes, method of 78 

Exclusion of sewer air from houses 14 

Final inspection by plumbing inspector 171 

Fixtures, as a basis of sizes of private sewers 32 

kitchen 96 

materials for , 93 

pantry 96 

Floor connections for water closet 110 

Floor drains 58 

Flow prevented by bends 19 

Flushing- of sewers, arrangements for 61 

frequency of 62 

Flushing tank, sewer, location of 62 

necessary capacity of 63 

water supply for 64 

Forms of traps 133-134 

Foundation slope for sewer, how obtained 20 

Four-inch sewer, closet capacity of..^ 71 

Fresh air inlet, location of 51 

Friction in pipes, cause of back pressure 147-148 

Germs, fever, how liberated from sewers 16 

Glazing, why omitted from spigot end of sewer pipe.. 40 

Grease traps, construction of 98-99 

location of 98 

object of 97 

vent pipe for 100 

where necessary 97 

Grease traps, care of by occupant of building 194 

Heating local vents, reason for 129 

Hopper closet described 105 

Hydrostatic test for roughing-in work 87-88-89 

Impermeability of sewers essential 16 

Inclination of private sewers 33 

Inside sewers 55 

connection with outside sewer 57 

Inspection and test, final 168 

points to be noted 171 

Interceptors 132 

grease, construction of 98-99 

location of 98 

object of '. 97 

vent pipe for 100 

where necessary 9 7 

201 



Page 

Iron pipe joints, how made 40 

Iron sewers, advantages of 21 

lasting qualities of 22 

Irrigation as applied to sewage disposal 175 

Jointing sewer pipes 36 

Joints, iron pipe, how made 40 

Joints of earthenware sewers, proper cement for.... 39 

why oakum precedes cement 38 

Kitchen fixtures 96 

Kitchen sinks, construction of 96 

Lateral connections, materials for 81 

Latrines described 119-120 

objections to 121-122 

term denned 118 

Laying sewer pipes 36 

Lead, where and how used 94 

Lighting of toilet room 130 

Local vents 128 

heating of 129 

where necessary . . . : 128-129 

Location of fresh air inlet 51 

main trap 48 

sewers, plans necessary for 18 

vertical soil and waste pipes 66 

Loss of seal in traps 137 

in trap by evaporation 148-149 

Main trap, air inlet 45 

controversy regarding 41 

danger of siphonage remote 45 

effect on siphonage of other traps 46 

to prevent freezing- of water in 44 

objections to 42 

utility of 43 

without manhole, construction of 49-50 

Making curves, method of 19 

Materials for lateral connections 81 

soil, waste and vent pipes 66 

Maximum and minimum size of sewers for ordinary 

buildings 29 

Metals for plumbing fixtures, qualifications of 93 

Method of making curves, proper and improper 19 

testing roughing-in work 86 

Minimum inclination for self cleansing sewers 34 

Normal amount of sewage per person per day 27 

202 



Page 

Objections to curves and- bends 19 

Office building's, size of soil pipes for C9 

Outside sewers 18 

Oxidation of organic matter in sewers 14 

Pipes, branch, connection with vertical stack 83 

branch waste, access openings S4 

branch waste, sizes of ■.-.-. S2 

branch waste, under floors not desirable S4 

cast iron, weight of 25 

earthenware sewer, qualities of 24 

iron sewer, qualities of 23 

joints, iron, how made 40 

soil, rules governing size of, in cities 73-74 

soil and waste, supports for 79-81 

stoneware, minimum thickness of 24 

vent 66 

Placard for toilet rooms 193 

Plan of proposed work, why necessary 18 

Plugs, clean-out, concealed 58 

Pan closets, described 102 

Pantry fixtures 96 

Pantry sinks, construction of 96 

Peppermint test 168 

objection to 169 

precaution while making 169 

Plumbing fixtures and accessories, materials for 93 

Plunger closet described 104 

Pneumatic test for roughing-in work 87, 90, 91 

Porcelain, qualification of, for fixtures 93 

Private sewers, how connected with main sewer 35 

Private toilet rooms 101 

Proper foundation slope, how to obtain 20 

Proper mimimum thickness 'of stoneware pipes 24 

Proper weights of cast iron sewer pipe 25 

Provision for testing sewer 36 

Public building, care of plumbing in 193 

Public toilet rooms, special requirements of 115 

Public toilet rooms 114 

Purification of sewage, how effected in surface irriga- 
tion 179 

in sub-surface irrigation 179 

Purification plants 175 

construction of . 179 

care of 195 

203 



Page 

Qualifications of metals for plumbing fixtures 93 

Railroad station urinals 125 

Rainfall, calculation of 30 

maximum amount necessary to provide for 31 

on roofs and lots, to estimate 30 

removal 29 

Refrigerators, drainage of to sewer 100 

Relation of number of closets to size of sewers 71 

Re-sealing traps 165 

apparatus for testing 167 

tests of 165-166 

Roofwater, removal of 53 

Roughing-in, hydrostatic test 86 

pneumatic test 86 

smoke test machine 91 

test 85 

tests, methods of 86 

Round pipe traps 135 

Rules governing sizes of soil pipes in large cities. .73-74 

Rust in fixture vent pipes, danger of 153 

School building urinals 126 

Septic tanks . 183-189 

component parts of 184 

importance of correct construction 184 

Sewage, decomposition of 13 

disposal of, by septic tank 183-184-186 

disposal of, in unsewered localities 174 

disposal of, for isolated buildings 175 

disposal of, by irrigation 175 

in cesspools, why unsanitary. 182 

irrigation beds, cropping of 177 

normal amount per person per day 27 

systems, in unoccupied buildings, dangers from. 195-196 

Sewer air, effects on health 14 

four-inch, closet capacity of 71 

flushing tanks, location of 62 

flushing tanks, necessary capacity of 63 

flushing tanks, regular examination of. . ; 194 

laying, in sections, bad practice 20 

materials, importance of strength and durability. . 17 

pipe, cast iron, weight of 25 

pipe, earthenware, to select best 25 

pipe glazing, why omitted from spigot ends 40 

204 



Page 

Sewer pipe, iron, how to protect from corrosion 23 

pipe, importance of even bearing for 38 

pipe jointing 36 

pipe laying 94 

pipe laying in sections, bad practice 64 

trench, time to dig 19 

Sewers, approximate inclination of 28 

arrangements for flushing of 61 

closet discharge, capacity of 71 

considerations governing construction of 13 

dissemination of infection through 15 

earthenware, objections to 21 

earthenware, when preferred 22 

earthenware, lasting qualities of 22 

earthenware and iron compared 23 

earthenware, cement for joints of 39 

frequency of flushing of 62 

fever germs, how liberated from 16 

impermeability of essential 16 

importance of accessibility 52 

inside 55 

inside, access openings for 57 

inside, connections with outside sewer 57 

iron, advantage of 21 

location of, plans necessary for 18 

materials for construction of 21 

maximum and minimum for ordinary buildings... 29 

outside IS 

oxidation of organic matter in 14 

private, depth of 32 

private, fixtures as a basis of size of 32 

private, inclination of 33 

private, velocity required for 34 

proper working of, responsibility of occupant. ... 191 

provision for cleaning 53 

relation of number of closets to size of 71 

self cleansing, minimum inclination of 34 

soundness of responsibility of owner to maintain 190 

Shower Baths 127 

Simplicity iTi sewer construction, reasons for 16 

Sinks, kitchen, construction of 96 

in cellars, danger of 95 

pantry, construction of 96 

205 



Page 

Sinks, slop '. 114 

Siphonage in traps 138 

deductions from experiments on 140-141 

Siphonage in main trap. 45-46 

Siphonage of traps by falling water in vertical pipes. 76 

Siphon jet closet described 107-108 

Six-inch sewer, closet capacity of 71 

Size and inclination of inside sewers 56 

Size and inclination of sewers, considerations governing 27 
Size of sewers and number of closets, relation of . . . . 72 

soil pipe for apartment building 69 

soil pipe for office building 69 

waste pipe for apartment building 69 

waste pipes for office building. 69 

Sizes of branch soil or waste pipes 82 

soil pipes required in various large cities 73-74 

soil, waste, and vent pipes 67, 69 

soil and waste pipes, rule for calculating. . 69-70, 72 

Slate, qualifications of, for fixtures 94 

Slop sinks 114 

construction of ..... ..-.-. 114 

location of trap 114 

Smoke test 168 

machine 91 

precautions while making 170-171 

Soapstone, qualifications of, for fixtures 94 

Soil pipe and water closet connection, how made. . 109-110 

extension above roof , . , . 76-77 

for apartment buildings, size of 69 

vertical, location of 66 

Soil, waste and vent pipes in smoke flues not desirable 66 
Soundness of sewers, responsibility of owner to 

maintain 190 

Special means of flushing, when necessary 34 

Steel, qualifications of, for fixtures 93 

Stoneware pipes, minimum thickness of 24 

Subsequent tests and inspection, buildings that require 172 

official and unofficial 171-172 

causes that make necessary 173 

Subsoil drains not connected with main sewer 54 

Subsoil water, removal of 53 

Sub-surface and surface sewage irrigation, difference 
between 179 

206 



Page 

Sub-surface irrigation for sewage disposal 177-178 

general plan of 178 

Suction, greatest, in waste pipes, when produced. .143, 144 

Surface irrigation for sewage disposal 176 

Surface water, removal of 53 

Supports for cast iron vertical soil pipes 80-81 

vertical soil and waste pipes 79 

Test, inspection, final 168 

Testing plugs, how to provide for 37 

Thickness of stoneware pipes, proper minimum 24 

Tin, sheet, where and how used 94 

Toilet rooms: floor, catch basin and trap 60 

placard for 193, 194 

public 114 

private 101 

lighting of 130 

Trap "bell," why unsatisfactory 59 

Trap and catch basin for removal of surface water. ... 60 

Trap, cleanout 136 

main, air inlet 45 

main, controversy regarding 41 

main, danger of siphonage remote 45 

main, effect on siphonage of other traps 46 

main, objections to 42 

main, to prevent freezing of water in 44 

main, utility of ." 43 

vent, anti-siphon, described 163-164 

vent, experiments relating to 142-143 

vent, chief objection to 162 

vent, to obviate stoppage by grease 163 

Trapping of public sewers by openings at grade 

objectionable 46 

Traps 132 

a necessary evil 48 

back pressure in, to prevent 147 

back venting of, not absolutely reliable 161 

care of by occupant of building 192 

causes of back pressure in 146 

evaporation in, per day 150 

experiments in relation to siphonage 138-139 

for fixtures 134 

forms of 133 

general plan of ventilation 152 

207 



Page 

Traps, loss of seal by back pressure 145 

loss of seal by capillary attraction 151 

loss of seal by evaporation 148-149 

loss of seal in 137 

principal method to protect water seal 152 

re-sealing 165 

re-sealing, tests of 165-166 

round pipe 135 

siphonage in 138 

ventilated safe against siphonage 140 

where necessary 133 

where unnecessary 133 

Trench, filling in, precaution for 92 

Trench, sewer, how to form proper slope 20 

time to dig 19 

importance of even slope 20 

Trough closets 116 

Trough closets, why inferior 117 

Underground vs. hanging pipes 56 

Urinals, construction of 123 

principal types 123-125 

railroad station 125 

school building 126 

Vacuum, greatest in waste pipes, when produced. 143-144 

Valve closet described 103 

Velocity required for private sewers 34 

Velocity of sewage caused by gravity in high build- 
ing 75 

Vent pipe, extension above roof 76-77 

grease interceptor 100 

size and length to protect S. trap 144 

sizes, Cleveland, Ohio, table of 156 

pipes, advantages of direct connection to sewer. . 47 

pipes, clogging of 159-160 

provisions of plumbing codes regarding 155-156 

size of 154-155 

Vents in branch pipes not necessary 83 

local, reason for heating 129 

local, when necessary 128-129 

trap, to obviate stoppage by grease 163 

trap, objections to 157-158 

Ventilation of fixture traps, general plan of 152 

of toilet room 131 

208 



Vertical soil and waste pipes, supports for 79 

Page 
waste pipes, determination of sizes difficult.... 75 

Wash basins 113 

desirable form of overflow 113 

proper fitting's for 113 

size of waste pipe for 113 

Washout closet described 106 

Waste from cistern, disposition of 65 

Waste pipes, branch, access openings 84 

extension above roof 76-77 

for apartment buildings, size of 69 

for bath tub, size of 112 

vertical, location of 66 

Water, amount necessary for domestic purposes 27 

Water closets, development of 102 

floor connections 110-111 

how to connect with soil pipe 109 

hopper type 105 

in cellars, location and type of 95 

pan type 102 

plunger type 104 

requirements and construction of 101 

setting points to observe 109 

siphon type 107-108 

valve type 103 

wash-out type 106 

Water seal 132 

of trap, to protect 152 

Weights of cast iron sewer pipe 25 

Weight of wrought iron sewer pipe....." 26 

Wrought iron pipe, weights of 26 

why not suitable 26 

precaution necessary, if used 26 

Zinc, not used in modern fixtures 94 



209 



H ' 



